wulfenite - crystal system
wulfenite - crystal system

Table of Gems Ordered by Crystal System


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 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.
wulfenite - crystal system
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. Wulfenites on a limonite matrix, San Juan Poniente Shaft, Ojuela Mine, Mapimi, Durango, Mexico. © Rob Lavinsky, www.iRocks.com. Used with permission.

"Amorphous" gems have no crystal structure.

Selected Minerals by Crystal System

CubicTetragonalHexagonalTrigonal8OrthorhombicMonoclinicTriclinicAmorphous
Almandine garnetAnataseAlgodoniteAgateAdamiteAegirineAlbiteAmber
AnalcimeApophylliteApatiteAmethystAeschyniteActinoliteAmazoniteGlass2
Andradite garnetCarletoniteAquamarineAmetrineAlexandriteAugeliteAmblygoniteMoldavite
BixbyiteCassiteriteBenitoiteAnkeriteAndalusiteAugiteAndesineObsidian
Boleite1ChalcopyriteBreithauptiteAventurineAnglesiteAzuriteAnorthiteOpal
ChromiteChioliteCacoxeniteBloodstoneAnhydriteBarytocalciteAxinitePetrified Wood
Cubic Zirconia (CZ)2Ekanite3CancriniteBruciteAragoniteBayldoniteBustamiteStrass
CupriteFergusonite3CatapleiiteCalciteBariteBerylloniteBytownite
Demantoid garnetHyacinth4ChlorapatiteCarnelianBismutotantaliteBrazilianiteCeruleite
DiamondIdocrase (Vesuvianite)CovelliteChalcedonyBoraciteCanasiteChabazite
Fabulite (Tausonite)LeuciteEmeraldChrysopraseBorniteCharoiteFowlerite
FluoriteMarialiteEttringiteCinnabarBrookiteChondroditeKurnakovite
Gadolinium gallium garnet (GGG)2MeioniteFluorapatiteCitrineCelestiteChrysocollaKyanite
GahniteMeliphaniteGosheniteCorundumCerussiteClinochloreLabradorite
GahnospinelMelliteGreenockiteDaviditeChambersiteClinoenstatiteLeucophanite
GalaxitePhosgeniteHeliodorDioptaseChildreniteClinohumiteMontebrasite
GarnetPowelliteHydroxylapatiteDolomiteChrysoberylColemaniteNambulite
GoldPyrolusiteJeremejeviteEudialyteCobaltiteCreediteOligoclase
Grossular garnetRutileLizarditeGaspéiteCordieriteCrocoitePectolite
HackmaniteSarcoliteManganapatiteHematiteDanburiteCryolitePeristerite
HaüyneScapoliteMilariteIlmeniteDescloiziteDatolitePyrophyllite
HelviteScheeliteMimetite5JasperDiasporeDickinsonitePyroxmangite
Hessonite garnetSellaiteMoissanite (Carborundum)6Linobate (Lithium niobate)2DumortieriteDiopsideRhodonite
KatoiteStolziteMorganiteLizarditeEnstatiteDurangiteSerandite
LangbeiniteTugtupiteNephelineMagnesiteEosphoriteEpidoteSerendibite
Lapis lazuliWarditeNiccoliteMeloniteEuchroiteEuclaseSunstone
LazuriteWulfenitePainiteMilleriteEuxenite3FriedeliteTalc
LeucograniteZircon3Precious Beryl7ParisiteGoethiteGadolinite3Tinzenite
MagnesiochromiteSimpsonitePhenakiteGrandidieriteGaylussiteTurquoise
MagnetiteSogdianitePrasioliteHambergiteGypsumUlexite
Melanite garnetSturmaniteProustiteHemimorphiteHedenbergiteWeloganite
Microlite3SugilitePyrargyriteHoltiteHerderite
PentlanditeTaafeiteQuartzHumiteHodgkinsonite
PericlaseThaumasiteRhodochrositeHyperstheneHornblende
PicotiteVanadiniteRose quartzKornerupineHowlite
PleonasteWurtziteRubelliteLawsoniteHuebnerite
PolluciteZinciteRubyLibetheniteHureaulite
PyriteSapphireLithiophiliteHurlbutite
Pyrope garnetSchlossmacheriteManganotantaliteInderite
RhodiziteSideriteMarcasiteJadeite
Rhodolite garnetSmithsoniteMordeniteKämmererite
SchorlomiteSmoky quartzNatroliteLazulite
SenarmontiteStichtiteNorbergiteLegrandite
SilverTiger's eyePeridotLepidolite
SodaliteTourmalinePrehniteLinarite
Spessartite garnetWillemitePurpuriteLudlamite
SphaleriteSamarskite3Malachite
SpinelScoroditeMesolite
ThorianiteSekaninaiteMonazite3
Topazolite garnetSepioliteMoonstone
Tsavorite garnetShattuckiteMuscovite
Uvarovite garnetShortiteNephrite
VilliaumiteSillimaniteNeptunite
Yttrium aluminum garnet (YAG)2SinhaliteOrthoclase
ZunyiteStibiotantalitePalygorskite
StrontianitePapagoite
SulfurPargasite
TantalitePetalite
Tanzanite (Zoisite)Phosphophyllite
TephroiteProsopite
ThomsonitePsilomelane
TopazPumpellyite
TriphylitePyrophyllite
VarisciteRealgar
WavelliteRichterite
WitheriteRinkite
ZektzeriteSanidine
Sapphirine
Scolecite
Serpentine
Sphene (Titanite)
Spodumene
Spurrite
Staurolite
Talc
Tremolite
Väyrynenite
Vivianite
Vlasovite
Whewellite
Wolframite
Wollastonite9
Xonotlite
Yugawaralite

Notes

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 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.

Additional Crystal System Information

For more detailed information, consult the individual gem listings as well as these International Gem Society articles:

What are Crystal Systems and Mineral Habits?

Descriptive Crystallography for Gemologists


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