Table of Gems Ordered by Crystal System

by International Gem Society

These butterscotch-colored wulfenite gemstones show their tetragonal crystal structure. Some gems in the tetragonal crystal system form as rectangular prisms with square terminations, like these. Others can take the shape of rectangular prisms with pyramidal terminations. Some form as dipyramids, two 4-sided pyramids joined at their bases. “Wulfenite” on a limonite matrix, San Juan Poniente Shaft, Ojuela Mine, Mapimi, Durango, Mexico. © Rob Lavinsky, www.iRocks.com. Used with permission.

The following table contains a selection of minerals gemologists may encounter as jewelry stones or gem specimens. The gems are sorted by their crystal system: cubic (isometric), tetragonal, hexagonal, trigonal, orthorhombic, monoclinic, and triclinic. “Amorphous” gems have no crystal structure.

Cubic	Tetragonal	Hexagonal	Trigonal	Orthorhombic	Monoclinic	Triclinic	Amorphous
Almandine	Anatase	Algodonite	Agate	Adamite	Aegirine	Albite	Amber
Analcite	Apophyllite	Apatite	Achroite	Aeschynite	Aegirine-Augite	Amazonite	Glass
Andradite	Carletonite	Aquamarine	Amethyst	Alexandrite	Actinolite	Amblygonite	Moldavite
Bixbyite	Chiolite	Benitoite	Amethyst Quartz	Andalusite	Allanite	Andesine	Obsidian
Boleite	Fergusonite	Beryl	Ametrine	Anglesite	Antigorite	Anorthite	Opal
Chromite	Hyacinth	Bixbite	Ankerite	Anhydrite	Augelite	Anorthoclase	Petrified Wood
Cuprite	Cassiterite	Breithauptite	Aventurine	Aragonite	Azurite	Axinite	Strass
Demantoid	Chalcopyrite	Cacoxenite	Bloodstone	Baryte	Barytocalcite	Bustamite
Diamond	Ekanite	Cancrinite	Blue Quartz	Bastite	Bayldonite	Bytownite
Fabulite	Leucite	Catapleiite	Brucite	Bismutotantalite	Beryllonite	Ceruleite
Fluorite	Marialite	Chlorapatite	Buergerite	Boracite	Bowenite	Chabazite
Gahnite	Meionite	Covellite	Bytownite	Bornite	Brazilianite	Ferro-Axinite
Gahnospinel	Melinophane	Emerald	Calcite	Bronzite	Canasite	Fowlerite
Galaxite	Mellite	Ettringite	Carnelian	Brookite	Chalcocite	Kurnakovite
GGG	Phosgenite	Fluorapatite	Cat’s-Eye Quartz	Celestine	Charoite	Kyanite
Gold	Powellite	Gold Beryl	Chalcedony	Cerussite	Childrenite	Labradorite
Garnet	Pyrolusite	Goshenite	Chromdravite	Chambersite	Chondrodite	Leucophanite
Grossularite	Rutile	Greenockite	Chrysoprase	Childrenite	Chromian Diopside	Magnesio-Axinite
Hackmanite	Sarcolite	Heliodor	Citrine	Chrysoberyl	Chrysocolla	Manganaxinite
Hauynite	Scapolite	Hydroxylapatite	Cinnabar	Cobaltite	Clinochlore	Microline
Helvite	Scheelite	Jeremejevite	Corundum	Cordierite	Clinochrysotile	Montebrasite
Hercynite	Sellaite	Lizardite	Davidite	Danburite	Clinoenstatite	Nambulite
Hessonite	Stolzite	Manganapatite	Dendritic Agate	Descloizite	Clinohumite	Natromontebrasite
Katoite	Synth. Rutile	Milarite	Dioptase	Diaspore	Clinozoisite	Oligoclase
Langbeinite	Tugtupite	Mimetite	Dolomite	Dumortierite	Colemanite	Pectolite
Lapis Lazuli	Vesuvianite	Moissanite	Dravite	Enstatite	Creedite	Peristerite
Lazurite	Wardite	Morganite	Elbaite	Eosphorite	Crocoite	Pyrophyllite
Leucogranite	Wulfenite	Nepheline	Eudialyte	Euchroite	Cryolite	Pyroxmangite
Magnesiochromite	Zircon	Nickeline	Gaspeite	Euxenite	Datolite	Rhodonite
Magnetite		Precious Beryl	Hawk’s-Eye	Ferrosilite	Dickinsonite	Sérandite
Melanite		Painite	Hematite	Forsterite	Diopside	Serendibite
Microlite		Simpsonite	Ilmenite	Goethite	Durangite	Sunstone
Pentlandite		Sogdianite	Indicolite	Grandidierite	Epidote	Talc
Periclase		Sturmanite	Jasper	Hambergite	Euclase	Tinzenite
Picotite		Sugilite	Liddicoatite	Hemimorphite	Friedelite	Turquoise
Pleonaste		Taafeite	Linobate	Holtite	Fuchsite	Ulexite
Pollucite		Thaumasite	Lizardite	Humite	Gadolinite	Weloganite
Pyrite		Vanadinite	Magnesite	Hypersthene	Gaylussite	Wollastonite
Pyrope		Wurtzite	Melonite	Kornerupine	Gypsum	Xonotlite
Rhodozite		Zincite	Millerite	Lawsonite	Hancockite
Rhodolite			Moss Agate	Libethenite	Hedenbergite
Schorlomite			Parisite	Lithiophilite	Herderite
Senarmontite			Phenakite	Manganotantalite	Hiddenite
Silver			Povondraite	Marcasite	Hodgkinsonite
Sodalite			Prase	Mordenite	Hornblende
Spessartine			Prasiolite	Natrolite	Howlite
Sphalerite			Proustite	Norbergite	Hübnerite
Spinel			Pyrargyrite	Pearl	Huréaulite
Synthetic Spinel			Quartz	Peridot	Hurlbutite
Thorianite			Rhodochrosite	Prehnite	Hyalophane
Topazolite			Rock Crystal	Purpurite	Hydroxylherderite
Tsavorite			Rose Quartz	Samarskite	Inderite
Uvarovite			Rubellite	Scorodite	Jadeite
Villiaumite			Ruby	Sekaninaite	Kämmererite
YAG			Sapphire	Sepiolite	Kunzite
Zirconia			Sardonyx	Shattuckite	Lazulite
Zunyite			Schlossmacherite	Shomiokite	Legrandite
			Schorl	Shortite	Lepidolite
			Siberite	Sillimanite	Linarite
			Siderite	Sinhalite	Ludlamite
			Smithsonite	Stibiotantalite	Malachite
			Smoky Quartz	Strontianite	Mesolite
			Stichtite	Sulfur	Monazite
			Tiger’s-Eye	Tanzanite	Moonstone
			Tsilaisite	Tantalite	Muscovite
			Tourmaline	Tephroite	Nephrite
			Uvite	Thomsonite	Neptunite
			Verdelite	Thulite	Orthoclase
			Willemite	Topaz	Palygorskite
				Triphylite	Papagoite
				Variscite	Pargasite
				Wavellite	Petalite
				Witherite	Phosphophyllite
				Yttrotantalite	Piemontite
				Zektzerite	Prosopite
				Zoisite	Psilomelane
					Pumpellyite
					Pyrophyllite
					Realgar
					Richterite
					Rinkite
					Sanidine
					Sapphirine
					Scolecite
					Scorzalite
					Serpentine
					Smaragdite
					Spodumene
					Spurrite
					Staurolite
					Talc
					Tawmawite
					Titanite
					Tremolite
					Väyrynenite
					Violane
					Vivianite
					Vlasovite
					Whewellite
					Williamsite
					Wolframite
					Wollastonite
					Xonotlite
					Yugawaralite