Gemstone Enhancements, Treatment and Care

Material Variety / Type Commercial Name Hardness Country of Origin Possible Modification & frequency of use Stability Care Advice
Andalusite Andalusite 7.5 Sri Lanka, Brazil, Russia, Canada, Australia, USA None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Apatite Apatite 5 Madagascar, Sri Lanka, Mynmar None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to scratching due to low hardness.  Wear with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Beryl Emerald                       (Green colour due to chromium +/- vanadium) Emerald 7.5 India, Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  If there are fissures or fractures.  Some stones cleave or fracture easily or are prone to the effect of brittleness e.g. rubbed facet edges.  Wear them with care.   Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Beryl Emerald                       (Green colour due to chromium +/- vanadium) Columbian Emerald 7.5 Columbia Colorless oils wax and resins in fissures (usually) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.  Fillers in voids/cavities, fissures, and/or open fractures, such as glass, plastic or hardened resin, can scratch more easily than the host stone or be more vulnerable to damage from heat or some acids (e.g. hydrofluoric).  Keep away from all chemicals, heat or abrasives.
Emerald                       (Green colour due to chromium +/- vanadium) Zambian Emerald 7.5 Zambia Dyed with the use of colored oils (occasionally) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Emerald                       (Green colour due to chromium +/- vanadium) Emerald 7.5 Columbia, Brazil Open fractures or cavities filled with hardened resins (commonly) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Aquamarine Aquamarine 7.5 Brazil, Africa None (Rarely) N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Aquamarine Aquamarine 7.5 Russia, Africa Heated (usually) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Goshenite Goshenite, or Colorless Beryl 7.5 Brazil, Canada, USSR None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Heliodor Heliodor, or Yellow Beryl, or Golden Beryl 7.5 Brazil, Russia, Madagascar, Ukraine, Namibia None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Heliodor Heliodor, or Yellow Beryl, or Golden Beryl 7.5 Brazil, Russia, Madagascar, Ukraine, Namibia Irradiated (usually) Variable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.
Morganite Morganite, or Pink Beryl 7.5 Brazil, Madagascar None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Morganite Morganite, or Pink Beryl 7.5 Brazil, Madagascar Heated (commonly) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
(other colours) Beryl with colour prefixes e.g., Green Beryl, Red Beryl etc. Brazil, Madagascar, USA (Red Beryl) None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Chrysoberyl Chrysoberyl 8.5 India, Brazil None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Chrysoberyl Cat's-eye, Cymophane Chrysoberyl Cat's-eye, or Cat's-eye 8.5 Sri Lanka, Brazil, China None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Alexandrite (definite colour change due to chromium) Alexandrite 8.5 Myanmar, Brazil, Sri Lanka, India None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Alexandrite (definite colour change due to chromium) Alexandrite Myanmar, Brazil, Sri Lanka, India Colorless oils wax and resins in fissures (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Corundum Ruby Ruby 9 Myanmar, Thailand, Pakistan, Afghanistan, Vietnam None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Ruby Ruby 9 Myanmar, India, Africa, Thailand Heated (usually) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Ruby Ruby 9 Myanmar, India, Africa, Thailand The healing of fissures (commonly) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Ruby Ruby 9 Myanmar, India, Africa, Thailand Glass filled open fractures and cavities (occasionally) Stable Fillers in voids/cavities, fissures, and/or open fractures, such as glass, plastic or hardened resin, can scratch more easily than the host stone or be more vulnerable to damage from heat or some acids (e.g. hydrofluoric).  Keep away from all chemicals, heat or abrasives.  Some stones are particularly susceptible to attack by acids.  Keep them away from acids.  Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Ruby Ruby 9 Myanmar, India, Africa, Thailand Lead glass filled open fractures and cavities (occasionally) Unstable Fillers in voids/cavities, fissures, and/or open fractures, such as glass, plastic or hardened resin, can scratch more easily than the host stone or be more vulnerable to damage from heat or some acids (e.g. hydrofluoric).  Keep away from all chemicals, heat or abrasives.  Some stones are particularly susceptible to attack by acids.  Keep them away from acids.  Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Ruby Ruby 9 Myanmar, India, Africa, Thailand Dyed (Occasionally) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Ruby Ruby 9 Myanmar, India, Africa, Thailand Introduction/diffusion of certain element(s) during the heating process (rarely) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Stones with superficial colour (or phenomena) surface layers are not suitable for re-cutting or re-polishing.  (Shallow)
Ruby Ruby 9 Myanmar, India, Africa, Thailand Colourless oil or unstable resin in fissures (occasionally) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to scratching due to low hardness.  Wear with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Ruby Ruby 9 Myanmar, India, Africa, Thailand Coloured oil in unstable fissures (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Star Ruby Star Ruby 9 Myanmar, India, Africa, Thailand None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Star Ruby Star Ruby 9 Myanmar, India, Africa, Thailand Heated Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Star Ruby Star Ruby 9 Myanmar, India, Africa, Thailand Dyed (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to scratching due to low hardness.  Wear with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Star Ruby Star Ruby 9 Myanmar, India, Africa, Thailand Colourless oil in fissures (occasionally) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Star Ruby (with asterism) Star Ruby 9 Myanmar, India, Africa, Thailand Introduction/diffusion of certain element(s) during the heating process (rarely) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Stones with superficial colour (or phenomena) surface layers are not suitable for re-cutting or re-polishing. (Shallow)
Sapphire (blue) Sapphire 9 Sri Lanka, India, Myanmar, Australia, Nigeria None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Sapphire (blue) Sapphire 9 Sri Lanka, India, Myanmar, Australia, Nigeria Heated (usually) N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Sapphire (blue) Sapphire 9 Sri Lanka, India, Myanmar, Australia, Nigeria Glass filled open fractures and cavities (rarely) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Fillers in voids/cavities, fissures, and/or open fractures, such as glass, plastic or hardened resin, can scratch more easily than the host stone or be more vulnerable to damage from heat or some acids (e.g. hydrofluoric).  Keep away from all chemicals, heat or abrasives.
Sapphire (blue) Sapphire 9 Sri Lanka, India, Myanmar, Australia, Nigeria Introduction/diffusion of certain element(s) during the heating process (rarely) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Stones with superficial colour (or phenomena) surface layers are not suitable for re-cutting or re-polishing. (Shallow)
Sapphire (blue) Sapphire 9 Sri Lanka, India, Myanmar, Australia, Nigeria Colourless oil or resin in fissures (occasionally) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to scratching due to low hardness.  Wear with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Star Sapphire (blue) Star Sapphire 9 Sri Lanka, India, Myanmar, Australia, Nigeria None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Star Sapphire (blue) Star Sapphire 9 Sri Lanka, India, Myanmar, Australia, Nigeria Introduction/diffusion of certain element(s) during the heating process (rarely) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Stones with superficial colour (or phenomena) surface layers are not suitable for re-cutting or re-polishing. (Shallow)
Star Sapphire (other colours) Star Sapphire with colour prefix 9 Sri Lanka, India, Myanmar, Australia, Nigeria None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Star Sapphire (other colours) Star Sapphire with colour prefix 9 Sri Lanka, India, Myanmar, Australia, Nigeria Heater (occasionally) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Star Sapphire (other colours) Star Sapphire with colour prefix 9 Sri Lanka, India, Myanmar, Australia, Nigeria Introduction/diffusion of certain element(s) during the heating process (rarely) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Stones with superficial colour (or phenomena) surface layers are not suitable for re-cutting or re-polishing. (Shallow)
Padparadscha (subtle mixture of pink and orange) Padparadscha, or Pink Orange Sapphire 9 Sri Lanka, Myanmar, Australia, Nigeria None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Padparadscha (subtle mixture of pink and orange) Padparadscha, or Pink Orange Sapphire 9 Sri Lanka, Myanmar, Australia, Nigeria Heated Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Pink-Orange Pink-Orange Sapphire 9 Sri Lanka, Myanmar, Australia, Nigeria Introduction/diffusion of certain element(s) during the heating process (commonly) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Stones with superficial colour (or phenomena) surface layers are not suitable for re-cutting or re-polishing. (Shallow)
Orange Orange Sapphire 9 Sri Lanka, Myanmar, Australia, Nigeria Introduction/diffusion of certain element(s)  during the heating process (usually) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Stones with superficial colour (or phenomena) surface layers are not suitable for re-cutting or re-polishing. (Shallow)
Other Colours Sapphire with colour prefix, or Corundum with colour prefix 9 Sri Lanka, Myanmar, Australia, Nigeria None stable (Some yellow are unstable) Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Other Colours Sapphire with colour prefix, or Corundum with colour prefix 9 Sri Lanka, Myanmar, Australia, Nigeria Heated (occasionally) stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Other Colours Sapphire with colour prefix, or Corundum with colour prefix 9 Sri Lanka, Myanmar, Australia, Nigeria Introduction/diffusion of certain element(s) during the heating process (rarely) stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Stones with superficial colour (or phenomena) surface layers are not suitable for re-cutting or re-polishing. (Shallow)
Other Colours Sapphire with colour prefix, or Corundum with colour prefix 9 Sri Lanka, Myanmar, Australia, Nigeria Irradiation to produce yellow colour (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones fade rapidly unless kept in the dark.
Danburite Danburite 7 Myanmar, USA, Mexico,Switzerland, Italy, Japan None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Diamond Diamond 10 South Africa, Australia, Russia, Brazil, USA, Sierra Leone, Zaire, Bostwana, Namibia, Canada --- --- ---
Diopside Diopside 5.5 Myanmar, Siberia (Russia), Pakistan, Austria, USA, Madagascar, Brazil, Canada, Sri Lanka None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Chrome Diopside (green color due to chromium) Chrome Diopside 5.5 Myanmar, Siberia (Russia), Pakistan, Austria, USA, Madagascar, Brazil, Canada, Sri Lanka None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to scratching due to low hardness.  Wear with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Violane (purple) Violan, or Violane 5.5 Myanmar, Siberia (Russia), Pakistan, Austria, USA, Madagascar, Brazil, Canada, Sri Lanka None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to scratching due to low hardness.  Wear with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Star Diopside Star Diopside 5.5 Myanmar, Siberia (Russia), Pakistan, Austria, USA, Madagascar, Brazil, Canada, Sri Lanka None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to scratching due to low hardness.  Wear with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Labradorite Labradorite 6 Labrador (Canada), Finland, Norway, former USSR None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Labradorite Labradorite 6 Labrador (Canada), Finland, Norway, former USSR Surface colourless waxing Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Labradorite with labradorescence Labradorite, or Spectrolite 6 Labrador (Canada), Finland, Norway, former USSR None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Labradorite with labradorescence Labradorite, or Spectrolite 6 Labrador (Canada), Finland, Norway, former USSR Surface colourless waxing Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to scratching due to low hardness.  Wear with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Labradorite with aventurescence Labradorite Sunstone 6 Labrador (Canada), Finland, Norway, former USSR None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to scratching due to low hardness.  Wear with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Garnet (group)
Almandine-Pyrope Rhodolite Rhodolite 6.5 South Africa, Brazil, Argentina Myanmar, Tanzania None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.
Grossular Tsavorite (green colour due to vanadium and/or chromium) Tsavorite, or Tsavolite, or Chrome Grossular 7 Kenya None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.
Hessonite Hessonite 7.25 Madagascar, Brazil, Canada, Russia and USA None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.
Pyrope Red Garnet Pyrope 7.25 South Africa, Argentina, Brazil, Australia, Myanmar, Switzerland None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.
Pyrope-Spessartine Pyrope-Spessartine, or Malaya Garnet or Umbalite 7 Sri Lanka, Madagascar, Brazil, Sweden, Australia, Myanmar and USA None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.
Spessartine Spessartine, Spessartite or Mandarin Garnet 7 Sri Lanka, Madagascar, Brazil, Sweden, Australia, Myanmar and USA None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.
Uvarovite Uvarovite 7.5 Rusia, Finland, Turkey and Italy None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.
Iolite See Cordierite --- --- --- ---
Jade Jadeite, Jadeite-jade, or A-Jade 7 Myanmar, guatemala, Japan and USA None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Jadeite, Jadeite-jade, or B-Jade 7 Myanmar, guatemala, Japan and USA Colourless polymer impregnated (commonly) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Jadeite, Jadeite-jade, or C-Jade 7 Myanmar, guatemala, Japan and USA Polymer colour impregnation following acid treatment (commonly) Variable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Jadeite, Jadeite-jade, or C-Jade 7 Myanmar, guatemala, Japan and USA Dyed (commonly) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Kyanite Kyanite, or Disthene 5 or 7 Myanmar, Brazil and Kenya None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to scratching due to low hardness.  Wear then with care.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Lapis Lazuli Lapis Lazuli Lapis Lazuli or Lapis 5.5 Afghanistan, Argentina, USSR and Chile None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are particularly susceptible to attack by acids.  Keep them away from acids.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Lapis Lazuli Lapis Lazuli or Lapis 5.5 Afghanistan, Argentina, USSR and Chile Surface colourless waxing (commonly) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are particularly susceptible to attack by acids.  Keep them away from acids.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Lapis Lazuli Lapis Lazuli or Lapis 5.5 Afghanistan, Argentina, USSR and Chile Dyed (commonly) Variable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are particularly susceptible to attack by acids.  Keep them away from acids.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Olivine Peridot Peridot 6.5 China, Brazil, Myanmar, Norway, Australia and South Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are particularly susceptible to attack by acids.  Keep them away from acids.
Peridot Peridot 6.5 China, Brazil, Myanmar, Norway, Australia and South Africa Colourless oil, wax or resins in fissures (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are particularly susceptible to attack by acids.  Keep them away from acids.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Peridot Peridot 6.5 China, Brazil, Myanmar, Norway, Australia and South Africa Filled open fractures with colourless hardened resin (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are particularly susceptible to attack by acids.  Keep them away from acids.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Opal (Play-of-colour) - may on the basis of body tone/transparency, or colour be described as: --- --- --- ---
Black to very dark Black Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Black to very dark Black Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa Impregnated with plastic or resin (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Black to very dark (transparent to near transparent) Black Crystal Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Black to very dark (transparent to near transparent) Black Crystal Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa Impregnated with plastic or resin (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
White White Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
White White Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa Impregnated with plastic or resin (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
White (transparent to near-transparent) Opal, or Water Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
White (transparent to near-transparent) Opal, or Water Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa Impregnated with plastic or resin (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Oolitic Opal Oolitic Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Oolitic Opal Oolitic Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa Impregnated with plastic or resin (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Orange to Red (transparent to translucent) Fire Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
(Attached to ironstone) Boulder Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
(Attached to ironstone) Boulder Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa Infusion of unhardened colourless substances into voids (occasionally) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
(in Matrix) Matrix Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
(in Matrix) Matrix Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa Sugar / acid treatment (commonly) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
White, porcelain-like Cacholong Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa Impregnated with plastic or resin (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Orange to Red Fire Opal 6 Australia, Brazil, Mexico, Czechoslovakia an Southern Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are prone to crack due to loss of structural water.  Keep away from heat and drying environment.  Some stones are prone to damage due to thermal shock.  Do not expose them to extreme temperature changes.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Quartz (macro-crystalline) --- --- --- --- ---
Amethyst Amethyst 7 Brazil, Sri Lanka, India, Uruguay, Madagascar, Germany, Australia, Namibia, Zambia None Stable (Some stones are unstable) Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.
Amethyst Amethyst 7 Brazil, Sri Lanka, India, Uruguay, Madagascar, Germany, Australia, Namibia, Zambia Heated (occasionally) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Amethyst-Citrine bicolor Ametrine 7 Brazil, Sri Lanka, India, Uruguay, Madagascar, Germany, Australia, Namibia, Zambia None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Amethyst-Citrine bicolor Ametrine 7 Brazil, Sri Lanka, India, Uruguay, Madagascar, Germany, Australia, Namibia, Zambia Heated Citrine (rarely) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Smoky Quartz Smoky Quartz, or Cairngorm, or Brown Quartz 7 Brazil, Madagascar, USA, Australia, Spain None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Smoky Quartz Smoky Quartz, or Cairngorm, or Brown Quartz 7 Brazil, Madagascar, USA, Australia, Spain Irradiated (occasionally) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Citrine Citrine, or Yellow Quartz 7 Brazil, Spain, Madagascar, USSR None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Citrine Citrine, or Yellow Quartz 7 Brazil, Spain, Madagascar, USSR Heated (usually) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Prasiolite Prasiolite, or Green Quartz 7 Brazil, Sri Lanka, India, Uruguay, Madagascar, Germany, Australia, Namibia, Zambia None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Prasiolite Prasiolite, or Green Quartz 7 Brazil, Sri Lanka, India, Uruguay, Madagascar, Germany, Australia, Namibia, Zambia Heated (usually) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Rock Crystal Rock Crystal 7 Brazil, Sri Lanka, India, Uruguay, Madagascar, Germany, Australia, Namibia, Zambia None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Rose Quartz Rose Quartz 7 Madagascar, Brazil, USA, USSR and Spain None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Aventurine Quartz Aventurine Quartz 7 Brazil, India, Russia None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Chalcedony or Agate --- --- --- ---
Chrysoprase (green colour due to inclusions of nickeliferous clay) Chrysoprase 7 Czechoslovakia, Australia, Brazil, Austria None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Chrome Chalcedony (green colour due to chromium) Chrome Chalcedony, or Mtorolite 7 Czechoslovakia, Australia, Brazil, Austria None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Chrysocolla Chalcedony (blue to blue-green colour due to inclusions of chrysocolla) Chrysocolla Chalcedony 7 Czechoslovakia, Australia, Brazil, Austria None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Cornelian Cornelian, or Carnelian 7 India None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Cornelian Cornelian, or Carnelian 7 India Heated (usually) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Cornelian Cornelian, or Carnelian 7 India Dyed (unusual) Variable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.
Sard Sard 7 Worldwide None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
(other uniform colours) Agate with colour prefix, or Chalcedony with colour prefix 7 Uruguay, Brazil, India, China, USA, Mexico, Madagascar, USA None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
(other uniform colours) Agate with colour prefix, or Chalcedony with colour prefix 7 Uruguay, Brazil, India, China, USA, Mexico, Madagascar, USA Dyed Black (always) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Agate with colour prefix, or Chalcedony with colour prefix 7 Uruguay, Brazil, India, China, USA, Mexico, Madagascar, USA Dyed Blue (always) Variable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.
Agate with colour prefix, or Chalcedony with colour prefix 7 Uruguay, Brazil, India, China, USA, Mexico, Madagascar, USA Dyed Green (always) Variable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.
(other uniform colours) Agate with colour prefix, or Chalcedony with colour prefix 7 Uruguay, Brazil, India, China, USA, Mexico, Madagascar, USA Dyed (commonly) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.
Banded Agate Banded Agate 7 Uruguay, Brazil, India, China, USA, Mexico, Madagascar, USA None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Banded Agate Banded Agate 7 Uruguay, Brazil, India, China, USA, Mexico, Madagascar, USA Dyed (usually) Fairly Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Fire Agate Fire Agate 7 Uruguay, Brazil, India, China, USA, Mexico, Madagascar, USA None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Iris Agate Iris Agate Uruguay, Brazil, India, China, USA, Mexico, Madagascar, USA None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Moss Agate Moss Agate, or Dendritic Agate Uruguay, Brazil, India, China, USA, Mexico, Madagascar, USA None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Onyx (straight layers of black and white) Onyx 7 Uruguay, Brazil, India, China, USA, Mexico, Madagascar, USA Dyed (always) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Jasper --- --- --- --- ---
Heliotrope Heliotrope, or Bloodstone 7 India, Venezuela, USA, Russia, France and Germany None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Multicoloured Jasper Multicoloured Jasper 7 India, Venezuela, USA, Russia, France and Germany None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Orbicular Jasper Orbicular Jasper 7 India, Venezuela, USA, Russia, France and Germany None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Japer, other colours Japer with other prefix 7 India, Venezuela, USA, Russia, France and Germany None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Japer, other colours Japer with other prefix 7 India, Venezuela, USA, Russia, France and Germany Dyed (commonly) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Scapolite Scapolite 6 None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Spinel Red Spinel 8 Myanmar, Sri Lanka, Madagascar, Afghanistan, Pakistan, Brazil None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Spodumene Kunzite Kunzite 7 Brazil, Madagascar, Myanmar, Mexico None Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Kunzite Kunzite 7 Brazil, Madagascar, Myanmar, Mexico Heated (commonly) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Hiddenite (green colour due to chromium) Hiddenite 7 Brazil, Madagascar, Myanmar, Mexico None Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
(other colours) Spodumene with colour prefix 7 Brazil, Madagascar, Myanmar, Mexico Green produced by irradiation (rarely0 Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Topaz White Topaz 8 Brazil, USA, Sri Lanka, Myanmar, Australia, Pakistan, Mexico, Japan, Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning. 
Pink Topaz 8 Russia, Pakistan, Brazil Heated to produce pink Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning. 
Sky, Swiss Blue Topaz 8 Brazil, USA, Sri Lanka, Myanmar, Australia, Pakistan, Mexico, Japan, Africa Irradiated and heated to produce blue (usually) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning. 
Imperial Topaz 8 Brazil, USA, Sri Lanka, Myanmar, Australia, Pakistan, Mexico, Japan, Africa Irradiated to yellow and orange (occasionally) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning. 
London Blue Topaz 8 Brazil, USA, Sri Lanka, Myanmar, Australia, Pakistan, Mexico, Japan, Africa Irradiated to produce greenish Blue (usually) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning. 
Green Topaz 8 Brazil, USA, Sri Lanka, Myanmar, Australia, Pakistan, Mexico, Japan, Africa Diffused to produce green (commonly) Stable (without re-cutting or re-polishing) Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Stones with superficial colour (or phenomena) surface layers are not suitable for re-cutting or re-polishing. (Shallow)
Mystic Topaz, and various colos of Topaz 8 Brazil, USA, Sri Lanka, Myanmar, Australia, Pakistan, Mexico, Japan, Africa Coated with very thin layers of metal oxide to provide various colours and to add special effects Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Tourmaline Group Colourless Colourless Tourmaline, or Achroite 7.5 None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Pink to Red Pink Tourmaline, or Red Tourmaline, or Rubellite 7.5 Brazil, Russia, Madagascar, Myanmar, East Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Pink to Red Pink Tourmaline, or Red Tourmaline, or Rubellite 7.5 Brazil, Russia, Madagascar, Myanmar, East Africa Heated (occasionally) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Pink to Red Pink Tourmaline, or Red Tourmaline, or Rubellite 7.5 Brazil, Russia, Madagascar, Myanmar, East Africa Irradiated (commonly) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Green due to chromium and/or vanadiem Chrome Tourmaline 7.5 Brazil, Madagascar None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Green Green Tourmaline, Verdelith or Verdelite 7.5 Brazil, Madagascar None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Green Green Tourmaline, Verdelith or Verdelite 7.5 Brazil, Madagascar Heated (commonly) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Green Green Tourmaline, Verdelith or Verdelite 7.5 Brazil, Madagascar Colourless Oils, resins and waxes in fissures (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Green Green Tourmaline, Verdelith or Verdelite 7.5 Brazil, Madagascar Cavities and fractures filled with colourless hardened substances (very rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Green to Blue due to copper Paraiba Tourmaline 7.5 Brazil, Madagascar None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Green to Blue due to copper Paraiba Tourmaline 7.5 Brazil, Madagascar Heated (commonly) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Green to Blue due to copper Paraiba Tourmaline 7.5 Brazil Filling of fissures with colourless oils, wax and resins (commonly) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Green to Blue due to copper Paraiba Tourmaline 7.5 Brazil Filling of cacities and fractures with colourless hardened substances (commonly) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Blue  Blue Tourmaline, or Indicolite 7.5 Siberia (Russia), Madagascar None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Blue  Blue Tourmaline, or Indicolite 7.5 Siberia (Russia), Madagascar Heated (commonly) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Other Colours Tourmaline with colour prefix 7.5 None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Other Colours Tourmaline with colour prefix 7.5 Heated to produce yellow/orange (rarely) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Other Colours Tourmaline with colour prefix 7.5 Irradiated to improve yellow/orange (rarely) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Parti-coloured: Parti-coloured, Bi-coloured, or tri-coloured Tourmaline 7.5 None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
(with red core and green rim) Watermelon Tourmaline 7.5 South Africa, Brazil, East Africa None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.
Turquoise Turquoise 6 Iran, Tibet, Mexico, USA, USSR, Chile, Australia None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Turquoise 6 Iran, Tibet, Mexico, USA, USSR, Chile, Australia Impregnated with plastic (commonly) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Turquoise 6 Iran, Tibet, Mexico, USA, USSR, Chile, Australia Surface colourless waxing (commonly) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Turquoise 6 Iran, Tibet, Mexico, USA, USSR, Chile, Australia Dyed (rarely) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Turquoise Matrix Turquoise Matrix, or Spider's Web Turquoise 6 Iran, Tibet, Mexico, USA, USSR, Chile, Australia See Turquoise above See Turquoise above Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are porous.  Do not allow contact with coloured fluids.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.  Modifications to stones with dye, oil, resin, wax or plastic are not permanent.  Keep away from all solvents (including various dish-washing liquids), chemicals and heat.
Zircon Zircon (with colour prefix) 7.5 Sri Lanka, Myanmar, Thailand, Combodia, Vietnam, Australia Heated to produce red and colourless (always) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
(Blue) Blue Zircon, or Starlite 7.5 Sri Lanka, Myanmar, Thailand, Combodia, Vietnam, Australia Heated to produce blue (always) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
(other colours) Zircon (with colour prefix) 7.5 Sri Lanka, Myanmar, Thailand, Combodia, Vietnam, Australia None N/A Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
(other colours) Zircon (with colour prefix) 7.5 Sri Lanka, Myanmar, Thailand, Combodia, Vietnam, Australia Heated to improve yellow (commonly) or green (occasionally) Unstable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones cleave or fracture easily or are prone to the effects of brittleness e.g. rubbed facet edges.  Wear them with care.  Some stones fade or revert to original colour when exposed to strong light.  Do not wear or leave them for extended periods under these conditions.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.
Zoisite Blue to violet Tanzanite 6.5 Tanzania Heated (almost always) Stable Normal care - With all gemstones and organic substances avoid rough handling and when not in wear, keep items of jewelry separated to avoid scratches.  Clean with warm soapy water and gentle brushing.  Ultrasonic cleaners should only be used with caution.  Some stones are susceptible to damage from ultrasonic cleaning.  Do not expose them to ultrasonic cleaning.