Your number one source for loose colored gemstones
Gem-Glossary
| Achroite | colorless variety of tourmaline. Hardness of 7 - 7,5 |
| Agate | translucent to opaque, semi-precious variety of chalcedony (quartz) |
| Alexandrite | rare mineral/gem (type of chrysoberyl) that appears to be different colors when viewed in artificial or natural light. |
| Almandine | reddish variety of garnet. Hardness of 6,5 - 7,5 |
| Amazonite | semi-precious stone (blue to bluish-green), variety of feldspar-family. |
| Amethyst | most popular quartz-variety (deep purple to pale lavender) |
| Ametrine | (partially purple/lavender and orange/yellow quartz-variety (amethyst and citrine). |
| Apatite | semi-precious mineral that occurs in many different colors, hardness of 5 |
| Aquamarine | very popular (blue) variety of the beryl-family |
| Aventurine | semi-precious, translucent variety of the quartz-family |
| Beryl | gemstone-group, including emerald, aquamarine, morganite, heliodor, bixbite and goshenite. |
| Birthstone | worldwide assigned stones to the months of the year |
| Brilliant Cut | faceted round cut (32 facets above the girdle, 24 facets below) |
| Cabochon | rounded cut (usually with a domed surface) - no facets |
| Carat | standard measure of gemstone-weight. One carat weights 0,2 gram. |
| Chalcedony | mostly milky or translucent semi-precious stones of the quartz-family, including cornelian, chrysoprase, onyx, jasper |
| Charoite | semi-precious,opaque mineral (purplish), only found in Russia |
| Chrome-Diopside | intense green-colored gemstone, hardness of 5 - 6 |
| Chrysoberyl | yellowish to green and brown colored gemstone, hardness of 8,5 |
| Chrysocolla | opaque, blue to bluish-green semi-precious mineral, hardness of 2 - 4 |
| Chrysoprase | most valued, semi-precious quarzt-variety (green) |
| Citrine | pale yellow to orange quarzt-variety. Hardness of 7 |
| Clarity | clearness of gemstones |
| Cornelian | semi-precious, tranlucent variety (reddish) of chalcedony-quartz. |
| Corundum | second hardest mineral on earth (hardness of 9). Depending on the color there are two precious varieties: ruby and sapphire |
| Crown | upper part of a faceted gemstone |
| Danburite | usually colorless gemstone, hardness of 7 - 7,5 |
| Demantoid | most expansive and rare variety (green) of garnet, hardness of 6,5 - 7,5 |
| Diamond | precious gemstone, made of compressed carbon, hardness 10 |
| Doublet | gemstone made of two layers - the upper part is usually the precious stone, the bottom-part is semi-precious. |
| Emerald | precious green gemstone, variety of beryl. Hardness of 7,5 - 8 |
| Enhanced | gemstones will be treated to improve the color or clarity. Heat-treatment is very common, all other methods (irradiation, coating, oiling, diffussion etc) have to be declared. |
| Facetting | cutting and polishing of the gemstone surface |
| Fancy Diamond | colored diamonds (all colors, except white), hardness of 10 |
| Fancy cut | Unusual cut (faceted or cabochon) |
| Feldspar | most common (semi-precious) mineral-family on earth, hardness of 4 - 6,5 |
| Fire Precious Opal | transparent opals (yellow, orange, red), mostly milky. Hardness of 5,5 - 6,5 |
| Fluorite | semi-precious mineral that occurs in many colors, hardness of 4 |
| Garnet | group of minerals/gems that occurs in a wide range of colors. Hardness of 6,5 - 7,5 |
| Gemstone | rare, valuable and attractive mineral (usually faceted) |
| GIA | Gemological Institute of America |
| Goshenite | Colorless variety of beryl. Hardness of 7,5 - 8 |
| Grossular | Variety of garnet, hardness of 6,5 - 7,5 |
| GLA | Gem Lab Austria (Vienna) |
| Hematite | opaque, silver to black colored semi-precious stone, hardness of 6,5 |
| Hessonite | Variety of garnet, hardness of 6,5 - 7,5 |
| Hiddenite | yellow to green variety of the mineral spodumene, hardness of 6,5 - 7 |
| IGI | International Gemological Institute |
| Imperial Topaz | most valuable topaz-variety (golden-orange-pinkish), hardness of 8 |
| Indicolite | blue variety of tourmaline. |
| Iolite | blue mineral/gem with strong pleochroism, hardness of 7 - 7,5 |
| Irradiation | radiation-treatment to enhance colors of gemstones |
| Jade | semi-precious stone, often set as cabochon in best (green & translucent) quality. Hardness of 6 - 7 |
| Jasper | semi-precious stone, variety of quartz. Hardness of 6,5 - 7 |
| Kunzite | pink variety of the mineral spodumene, hardness of 6,5 - 7 |
| Kyanite | blue gemstone, mostly with color-zoning. Hardness 4,5 - 6 - very difficult to cut! |
| Labradorite | variety of the semi-precious feldspar-group (plagioclase). Hardness 6 - 6,5 |
| Lapislazuli |
opaque, blue semi-precious stone. Hardness of 5,5 |
| Mandarin-Garnet | orange variety of garnet (spessartite-group), hardness of 7 - 7,5 |
| Malachite | opaque, semi-precious stone (green-banded), Hardness of 4 |
| Mohs-scale | This scale shows a chart of relative hardness of various
minerals (1 = softest, 10 = hardest). Hardness Example
1
talc
2
gypsum
2.5
fingernail
3
calcite, a penny
4
fluorite
5
apatite
5.5-6.5
most glass
6
feldspar (spectrolite)
7
quartz (amethyst, citrine, agate)
6.5-7.5
steel file
7.5
garnet
8
beryl (emerald, aquamarine)
9
corundum (ruby, sapphire)
10
diamond |
| Morganite | pink variety of beryl. Hardness of 7,5 - 8 |
| Moonstone | semi-transparent to translucent variety of feldspar. It occurs in different colors (white, pale yellow, grey, orange, brown and reddish) Hardness of 6 - 6,5 |
| Obsidian | semi-precious stone (transparent - opaque), hardness of 5 |
| Onyx | semi-precious variety of chalcedony (quartz). Hardness of 6,5 - 7 |
| Precious Opal | very popular gemstone (3 major types), containing water (!). Hardness of 5,5 - 6,5 |
| Opaque | light is not possible to pass through (no brilliance) |
| Padparadscha | beautiful, pinkish-orange sapphire-color, rare found in Sri Lanka |
| Peridot | green gemstone of vivid color. Hardness of 6,5 - 7 |
| Pleochroism | the property of having more than only one color, especially when the gemstone is viewed from different angles |
| Precious Stone | rare and valuable gemstone |
| Pyrope | reddish variety of garnet. Hardness of 6,5 - 7,5 |
| Pyrite | opaque, semi-precious stone (metallic). Hardness of 6 - 6,5 |
| Quartz | the second common mineral on earth, including amethyst, ametrine, citrine, rose quarz, aventurine, rock crystal, chalcedony, chrysoprase and many others |
| Rhodolite | pinkish-red variety of garnet (combination of pyrope and almandine). Hardness of 7 - 7,5 |
| Rock Crystal | colorless variety of quartz, also called white quarz. Hardness of 7 |
| Rose Quartz | pale pink to pink variety of quartz (mostly silky). Hardness of 7 |
| Rubellite | reddish variety of tourmaline. Hardness of 7 - 7,5 |
| Ruby | reddish variety of corundum. Actually one of the most expansive gemstones. Hardness of 9 |
| Rutilated Quartz | Variety of quartz, containing fine needles of rutile-crystals. |
| Sapphire | all color-varieties of corundum, except red. One of the most popular and expansive gemstones. Hardness of 9. |
| Sillimanite | rare gem/mineral, ranging in color from colorless, yellow, greyish, greenish to brown. Hardness of 6,5 - 7,5 |
| Smoky Quartz | brownish (smoky) variety of quarz. Hardness of 7 |
| Sodalite | blue and opaque, semi-precious stone, Hardness of 5,5 - 6 |
| Spessartite | reddish or orange variety of garnet. Hardness of 7 - 7,5 |
| Spinel | attractive gemstone which ranges in color from yellow to black. Hardness of 8 |
| Sunstone | reddish-orange (metallic) variety of feldspar (oligoclase). Hardness of 6 |
| Tanzanite | exclusive bluish-purple gemstone from Tanzania in East-Africa. Hardness of 6,5 - 7 |
| Tsavorite | exclusive green variety of garnet (grossular-group). Hardness of 6,5 - 7,5 |
| Tiger´s Eye | yellowish-brown, opaque variety of the quarz-family. Hardness of 7 |
| Topaz | popular gemstone, ranges in color from colorless to yellow, to orange to pink and brown. Hardness of 8 |
| Tourmaline | the only gemstone which occurs in all colours. Hardness of 7 - 7,5 |
| Translucent | light is able to pass through, but it is scattered |
| Transparent | light is able to pass through without any diffusing |
| Turquoise | semi-precious, opaque stone with typical color. Hardness of 6 |
| Unakit | opaque, semi-precious stone (containing granite, epidote and feldspar). Hardness of 6,5 - 7 |
| Zircon | natural gemstone, occuring in many different colours. Hardness of 6,5 - 7,5 |
Last Update on 01/07/21
