This table contains a selection of minerals gemologists may encounter as jewelry stones or gem specimens. The gems are sorted by their crystal system.
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The gems are sorted by their crystal system: isometric (cubic), tetragonal, hexagonal, trigonal, orthorhombic, monoclinic, and triclinic.
Amorphous gems have no crystal structure.
1. Boleite has also been classed as a tetragonal, pseudo-cubic crystal.
2. Synthetic, lab-created material.
3. May lose their crystalline structure due to natural radiation (metamictization).
4. In modern times, hyacinth or jacinth usually refers to reddish brown zircon, which belongs to the tetragonal crystal system. However, historically it has also been used to refer to hessonite (cubic), topazes (orthorhombic), and various other gemstones.
5. Mimetite has also been classed as a monoclinic, pseudo-hexagonal crystal.
6. Both natural and synthetic stones. (Natural moissanite crystals are too small to cut).
7. Any beryl variety not aquamarine, emerald, goshenite, heliodor, morganite, or red.
8. Many of the materials mineralogists have classed as trigonal crystals have been classed by gemologists as hexagonal crystals in a trigonal subclass. Thus, you'll find many of the gems listed here classed as hexagonal in their individual gem listings.
9. Wollastonite has monoclinic and triclinic polytypes.
For more detailed information, consult the individual gem listings as well as these International Gem Society articles:
What are Crystal Systems and Mineral Habits?
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The gems are sorted by their crystal system: isometric (cubic), tetragonal, hexagonal, trigonal, orthorhombic, monoclinic, and .
Amorphous gems have no crystal structure.
| Cubic | Tetragonal | Hexagonal | Trigonal8 | Orthorhombic | Monoclinic | Triclinic | Amorphous |
| Almandine garnet | Anatase | Algodonite | Agate | Adamite | Aegirine | Albite | Amber |
| Analcime | Apophyllite | Apatite | Amethyst | Aeschynite | Actinolite | Amazonite |
1. Boleite has also been classed as a tetragonal, pseudo-cubic crystal.
2. Synthetic, lab-created material.
3. May lose their crystalline structure due to natural radiation (metamictization).
4. In modern times, hyacinth or jacinth usually refers to reddish brown zircon, which belongs to the tetragonal crystal system. However, historically it has also been used to refer to hessonite (cubic), topazes (orthorhombic), and various other gemstones.
5. Mimetite has also been classed as a monoclinic, pseudo-hexagonal crystal.
6. Both natural and synthetic stones. (Natural moissanite crystals are too small to cut).
7. Any beryl variety not aquamarine, emerald, goshenite, heliodor, morganite, or red.
8. Many of the materials mineralogists have classed as trigonal crystals have been classed by gemologists as hexagonal crystals in a trigonal subclass. Thus, you'll find many of the gems listed here classed as hexagonal in their individual gem listings.
9. Wollastonite has monoclinic and triclinic polytypes.
For more detailed information, consult the individual gem listings as well as these International Gem Society articles:
| Glass2 |
| Andradite garnet | Carletonite | Aquamarine | Ametrine | Alexandrite | Augelite | Amblygonite | Moldavite |
| Bixbyite | Cassiterite | Benitoite | Ankerite | Andalusite | Augite | Andesine | Obsidian |
| Boleite1 | Chalcopyrite | Breithauptite | Aventurine | Anglesite | Azurite | Anorthite | Opal |
| Chromite | Chiolite | Cacoxenite | Bloodstone | Anhydrite | Barytocalcite | Axinite | Petrified Wood |
| Cubic Zirconia (CZ)2 | Ekanite3 | Cancrinite | Brucite | Aragonite | Bayldonite | Bustamite | Strass |
| Cuprite | Fergusonite3 | Catapleiite | Calcite | Barite | Beryllonite | Bytownite |
| Demantoid garnet | Hyacinth4 | Chlorapatite | Carnelian | Bismutotantalite | Brazilianite | Ceruleite |
| Diamond | Idocrase (Vesuvianite) | Covellite | Chalcedony | Boracite | Canasite | Chabazite |
| Fabulite (Tausonite) | Leucite | Emerald | Chrysoprase | Bornite | Charoite | Fowlerite |
| Fluorite | Marialite | Ettringite | Cinnabar | Brookite | Chondrodite | Kurnakovite |
| Gadolinium gallium garnet (GGG)2 | Meionite | Fluorapatite | Citrine | Celestite | Chrysocolla | Kyanite |
| Gahnite | Meliphanite | Goshenite | Corundum | Cerussite | Clinochlore | Labradorite |
| Gahnospinel | Mellite | Greenockite | Davidite | Chambersite | Clinoenstatite | Leucophanite |
| Galaxite | Phosgenite | Heliodor | Dioptase | Childrenite | Clinohumite | Montebrasite |
| Garnet | Powellite | Hydroxylapatite | Dolomite | Chrysoberyl | Colemanite | Nambulite |
| Gold | Pyrolusite | Jeremejevite | Eudialyte | Cobaltite | Creedite | Oligoclase |
| Grossular garnet | Rutile | Lizardite | Gaspéite | Cordierite | Crocoite | Pectolite |
| Hackmanite | Sarcolite | Manganapatite | Hematite | Danburite | Cryolite | Peristerite |
| Haüyne | Scapolite | Milarite | Ilmenite | Descloizite | Datolite | Pyrophyllite |
| Helvite | Scheelite | Mimetite5 | Jasper | Diaspore | Dickinsonite | Pyroxmangite |
| Hessonite garnet | Sellaite | Moissanite (Carborundum)6 | Linobate (Lithium niobate)2 | Dumortierite | Diopside | Rhodonite |
| Katoite | Stolzite | Morganite | Lizardite | Enstatite | Durangite | Serandite |
| Langbeinite | Tugtupite | Nepheline | Magnesite | Eosphorite | Epidote | Serendibite |
| Lapis lazuli | Wardite | Niccolite | Melonite | Euchroite | Euclase | Sunstone |
| Lazurite | Wulfenite | Painite | Millerite | Euxenite3 | Friedelite | Talc |
| Leucogranite | Zircon3 | Precious Beryl7 | Parisite | Goethite | Gadolinite3 | Tinzenite |
| Magnesiochromite | Simpsonite | Phenakite | Grandidierite | Gaylussite | Turquoise |
| Magnetite | Sogdianite | Prasiolite | Hambergite | Gypsum | Ulexite |
| Melanite garnet | Sturmanite | Proustite | Hemimorphite | Hedenbergite | Weloganite |
| Microlite3 | Sugilite | Pyrargyrite | Holtite | Herderite |
| Pentlandite | Taafeite | Quartz | Humite | Hodgkinsonite |
| Periclase | Thaumasite | Rhodochrosite | Hypersthene | Hornblende |
| Picotite | Vanadinite | Rose quartz | Kornerupine | Howlite |
| Pleonaste | Wurtzite | Rubellite | Lawsonite | Huebnerite |
| Pollucite | Zincite | Ruby | Libethenite | Hureaulite |
| Pyrite | Sapphire | Lithiophilite | Hurlbutite |
| Pyrope garnet | Schlossmacherite | Manganotantalite | Inderite |
| Rhodizite | Siderite | Marcasite | Jadeite |
| Rhodolite garnet | Smithsonite | Mordenite | Kämmererite |
| Schorlomite | Smoky quartz | Natrolite | Lazulite |
| Senarmontite | Stichtite | Norbergite | Legrandite |
| Silver | Tiger's eye | Peridot | Lepidolite |
| Sodalite | Tourmaline | Prehnite | Linarite |
| Spessartite garnet | Willemite | Purpurite | Ludlamite |
| Sphalerite | Samarskite3 | Malachite |
| Spinel | Scorodite | Mesolite |
| Thorianite | Sekaninaite | Monazite3 |
| Topazolite garnet | Sepiolite | Moonstone |
| Tsavorite garnet | Shattuckite | Muscovite |
| Uvarovite garnet | Shortite | Nephrite |
| Villiaumite | Sillimanite | Neptunite |
| Yttrium aluminum garnet (YAG)2 | Sinhalite | Orthoclase |
| Zunyite | Stibiotantalite | Palygorskite |
| Strontianite | Papagoite |
| Sulfur | Pargasite |
| Tantalite | Petalite |
| Tanzanite (Zoisite) | Phosphophyllite |
| Tephroite | Prosopite |
| Thomsonite | Psilomelane |
| Topaz | Pumpellyite |
| Triphylite | Pyrophyllite |
| Variscite | Realgar |
| Wavellite | Richterite |
| Witherite | Rinkite |
| Zektzerite | Sanidine |
| Sapphirine |
| Scolecite |
| Serpentine |
| Sphene (Titanite) |
| Spodumene |
| Spurrite |
| Staurolite |
| Talc |
| Tremolite |
| Väyrynenite |
| Vivianite |
| Vlasovite |
| Whewellite |
| Wolframite |
| Wollastonite9 |
| Xonotlite |
| Yugawaralite |
