Rock Forming Minerals
Quartz
Crystalline Varieties
** Milky quartz (Miners called it bull quartz)
** Amethyst
** Rose quartz
** Citrine
** Rock Quartz (clear, transparent, colorless)
** Ferruginous Quartz
Cryptocrystalline Varieties
**Chalcedony
**Agate
**Jasper
*Feldspar Group
K-spar Sub-Group
Microcline
** Amazonite
Orthoclase
** Adularia
Sanidine
Plagioclase (a solution series)
Albite
Anorthite
Andesine
Labradorite
*Amphibole Group
Actinolite-Tremolite
**Cryptocrystalline Variety found in the rock nephrite (Wyoming Jade)
Horneblende
Grunerite
Crocidolite (Rebeckite)
*Serpentine Group
Chrysotile
Lizardite
Antigorite
*Pyroxene Group
Augite
Diopside
Spodumene
Enstatite
*Mica Group
Biotite
Fuchsite
Lepidolite
Muscovite
Phlogopite
Olivine
*Garnet Group
Almandine
Pyrope-almandine
Pyrope
Spessartine
Calcite
Dolomite
Gypsum
** selenite (clear crystals)
** satin spar
** alabaster
Other Minerals
Common to Very Rare
Allanite
Ankerite
Anhydrite
*Apatite Group
Flourapatite
Hydroxylapatite (Dahllite**)
Aragonite
Andalusite
Arsenopyrite
Azurite
Autunite
Barite
Benjaminite^
Bertierite^
Beryl
** Emerald^
** Helidor^
**Aquamarine^
Bornite
Bournonite (Cog wheel ore)
Carnotite
Coffinite
Chalcocite
Chalcopyrite
Chromite
Chrysocolla
Clinochore
**Kammererite (A variety of Clinoclore)
Clinoptilolite
Columbite-Tantalite
Cordierite (**Iolite)
Corundum
** sapphire^
** ruby^
Native Copper^
Covellite
Cuprite
Diamond^
Epidote
Euxenite^
Fluorite
Galena
Native Gold
Grandidierite^
Graphite
Hematite
**Specularite— one of the varieties found in WY
Hemimorphite
Ilmenite
Ilsemannite^
Kyanite
Leucite^
“Limonite”
Manganese oxides
Manganite^
Magnetite
Marcasite
Mascagnite^^
Minyulite^
Monazite
Molybdenite
Orpiment
Phenakite^
Native Platinum^
Realgar (Lorandite)
Pectolite
Psilomelane
Pyrite
Pyrrhotite
Scheelite
Schroeckingerite (Dakeite)^
Serpentine Group
Chrysotile
Lizardite
Antigorite
Sheridanite^^
Siderite
Sillimanite
Native Silver^
Smithsonite^
Sperrylite^
Sphalerite
Starolite
Stromeyerite
Native Sulfur
Talc
Tenorite
Tetrahedrite
Tourmaline
**Schorl
Trona (Other minerals related to Trona include Eitelite^, Thermonatrite^, Shortite^)
Tschermigite^^
Uraninite
Variscite^
Vermiculite
Vivianite^
Wulfenite
*Zeolite Group
Anaclime
Clinoptilolite
Natrolite
Stilbite
Thompsonite^
Zoisite
** pink microcrystalline variety called Thulite
Note: Opal is amorphous and not considered a mineral. Amber, coal, asphaltum; gilsonite, ozokerite are organic compounds and not minerals. Bentonite is a mixture of clay minerals and considered a rock not a mineral.
Definitions:
*Mineral groups are 2 or more mineral species having identical or closely related structures. If the specific mineral species is not known or unable to be determined with available tools, they may be referred to with the group name (ie: an amphibole).
** A mineral variety is a variation in distinctive physical properties of a specific mineral species such as color, minor impurities, or habit. The different varieties of a given mineral species have the same base chemical composition.
^ Rare to extremely rare In Wyoming
^^ So rare, almost didn’t make list
References:
Root, F.K., 1977, Minerals and rocks of Wyoming: Geological Survey of Wyoming [Wyoming State Geological Survey] Bulletin 56, 84 p. (Revised from 1972.)
Hausel, W.D., 1986, Minerals and rocks of Wyoming: Geological Survey of Wyoming [Wyoming State Geological Survey] Bulletin 66, 117 p., 30 pls.
Hausel, W.D., Root, F.K., Jones, R.W., and Albert, K.G., 1988, Guide to some rocks and minerals of Wyoming: Geological Survey of Wyoming [Wyoming State Geological Survey] Miscellaneous Publication, 30 p.
Hausel, W.D., 2005, Minerals and rocks of Wyoming—A guide for collectors, prospectors, and rock hounds: Wyoming State Geological Survey Bulletin 72, 159 p.
Hausel, W.D., and Sutherland, W.M., 2000, Gemstones and other unique minerals and rocks of Wyoming—A field guide for collectors: Wyoming State Geological Survey Bulletin 71, 268 p. (Reprinted 2014.)
Nelson, Willis H., Prostka, Harold J., Williams, Frank E., Elliott, James E., Peterson, Donald L., 1980, Geology and mineral resources of the North Absaroka Wilderness and vicinity, Park County, Wyoming, USGS Bulletin 1447, U.S. Geological Survey, 101 p.
mindat.org various pages referencing Wyoming mineral occurrences, Accessed 10/2023 and 2/2022.
Gregory L. Jones personal collection and knowledge