| Gem |
Colour/Variety |
Possible enhancements |
Gemstone care |
| Amber |
All colours |
Heating treatment to improve colour and clarity. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
| Apatite |
|
None. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
| Beryl |
Heliodor |
Irradiated to improve colour. |
Basic jewellery care. |
|
Aquamarine, Morganite |
Heating treatment to improve colour and clarity. |
Basic jewellery care. |
|
Emerald |
Infused with colourless substances to improve surface uniformity. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
| Chalcedony |
Bloodstone, Blue Lace Agate, Chrysocolla, Chrysoprase, Jasper, Sardonyx, White |
None. |
Basic jewellery care. |
|
Black, Blue and Green |
Dyed. |
Basic jewellery care. |
|
Agate, Carnelian |
Heating treatment to improve colour. |
Basic jewellery care. |
| Charoite |
|
Coated with colourless substances to improve surface uniformity and durability. |
Do not use ultrasonic cleaning. |
| Chrysoberyl |
Alexandrite, Brown, Cat’s Eye, Cat’s Eye Alexandrite, Green, Yellow |
None. |
Basic jewellery care. |
| Corundum |
Ruby, Star Ruby |
Heating treatment to improve colour and clarity. Infused with colourless substances to improve colour and clarity. |
Basic jewellery care. |
|
Blue Sapphire, Iridescent, Colourless, Green, Orange, Yellow, Padparadscha, Pink, Violet Sapphires and Star Sapphire |
Heating treatment and/or irradiation to improve colour and clarity. Infused with colourless substances to improve colour and clarity. |
Basic jewellery care. |
| Diamond |
|
None. |
Basic jewellery care. |
| Feldspar |
Labradorite, Moonstone, Spectrolite, Sunstone |
None. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
|
Amazonite |
Coated with colourless substances to improve surface uniformity. |
|
| Fluorite |
|
Heating treatment to improve colour. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
| Garnet |
Almandite, Colour Change, Andradite, Grossular, Hessonite, Malaya, Pyrope, Rhodolite, Spessartite, Tsavorite |
None. |
Avoid sudden temperature changes. |
| Iolite |
|
None. |
Do not use ultrasonic cleaning. |
| Jade |
Black, White Jadeite, Green and Lavender, Black and Green Nephrite |
Coated with colourless substances to improve surface uniformity. |
Do not use ultrasonic cleaning. |
| Kyanite |
Blue |
None. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
| Lapis Lazuli |
|
Coated with colourless substances to improve surface uniformity and durability. |
Do not use ultrasonic cleaning. Avoid contact with cosmetics, hairspray, perfume or household chemicals. |
| Malachite |
|
Coated with colourless substances to improve surface uniformity and durability. |
Do not use ultrasonic cleaning. Avoid contact with cosmetics, hairspray, perfume or household chemicals. |
| Opal |
Black, Blue, Boulder, Cachalong, Chrysopal, Crystal, Fire, Opalite, Pink, Prase, White, Yellow |
Coated with colourless substances to improve surface uniformity and durability. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
| Cultured Pearls |
Saltwater: Akoya, Mabe (assembled) |
Bleached and dyed to improve uniformity of colour. |
Have strands cleaned and re-strung annually if worn regularly. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
|
Keshi, South Sea Golden, South Sea White, Tahitian |
Bleached and dyed to improve uniformity of colour. Covered to protect the natural organic material. |
Have strands cleaned and re-strung annually if worn regularly. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
|
Freshwater |
Bleached and dyed to improve uniformity of colour. |
Have strands cleaned and re-strung annually if worn regularly. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
| Natural Pearls |
Freshwater, Saltwater |
Bleached and dyed to improve uniformity of colour. |
Have strands cleaned and re-strung annually if worn regularly. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
| Calcareous Concretions |
Conch, Melo Melo |
Polished to improve finish. |
Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
| Peridot |
|
None. |
Avoid contact with cosmetics, hairspray, perfume or household chemicals. Avoid contact with chlorate water. |
| Prenite |
|
Coated with colourless substances to improve surface uniformity. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
| Quartz |
Aventurine, Dumortierite, Pietersite, Quartzite, Rock Crystal, Rose, Rutilated, Tiger’s Eye, Tiger’s Iron, Tourmalinated |
None. |
Basic jewellery care. |
|
Amethyst, Citrine, Prasiolite, Smokey |
Heating treatment to improve colour. |
Basic jewellery care. |
| Rhodochrosite |
|
Coated with colourless substances to improve surface uniformity. |
Do not use ultrasonic cleaning. |
| Rhodonite |
|
Coated with colourless substances to improve surface uniformity. |
Do not use ultrasonic cleaning. |
| Shell |
Mother of Pearl |
Dyed. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
| Sodalite |
|
Coated with colourless substances to improve surface uniformity and durability. |
Do not use ultrasonic cleaning. Avoid contact with cosmetics, hairspray, perfume or household chemicals. |
| Spinel |
All colours |
None. |
Basic jewellery care. |
| Spodumene |
Kunzite |
Heating treatment and/or irradiation to improve colour. |
Do not use ultrasonic cleaning. Avoid direct sunlight. |
| Sugilite |
|
Coated with colourless substances to improve surface uniformity. |
Do not use ultrasonic cleaning. Avoid contact with household chemicals. |
| Topaz |
Imperial, Orange, Pink, Yellow |
Heating treatment and/or irradiation to improve colour. |
Basic jewellery care. |
| Tourmaline |
Chrome |
None. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes. |
|
Blue, Green, Indicolite, Paraiba, Yellow |
Heating treatment to improve colour and clarity. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes. |
|
Multicoloured, Pink, Purple, Rubellite, Watermelon |
Irradiated to improve colour. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes. |
| Turchese |
|
Coated with colourless substances to improve surface uniformity and durability. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes and contact with cosmetics, hairspray, perfume or household chemicals. |
| Unakite |
|
Coated with colourless substances to improve surface uniformity. |
Basic jewellery care. |
| Zircon |
All colours |
Heating treatment to improve colour. |
Do not use ultrasonic cleaning. |
| Zoisite |
Tanzanite |
Coated with colourless substances to improve surface uniformity. |
Do not use ultrasonic cleaning. Avoid sudden temperature changes. |
|
Ruby in Zoisite |
Coated with colourless substances to improve surface uniformity. |
Do not use ultrasonic cleaning. |
|
Thulite |
Coated with colourless substances to improve surface uniformity. |
Do not use ultrasonic cleaning. |
