Common Uranium Minerals Classified by Colors

Name

Chemical Composition

%U3O8ColorLusterHardnessSpecific Gravity SG

Characteristics & Occurrence

PitchblendeUranium oxide50-80Black (Grayish, Greenish)Pitch like Earthy, Dull or Glassy5-66-9In Veins; often with Sulphides of Cobalt, Nickel,Silver, Bismuth or Yellow Secondary Uranium Minerals. Never Brownish or Reddish.
UraniniteUranium oxide65-85Black (Grayish, Greenish, Brownish)Pitch like Dull or Glassy5-68-10Small Amounts in Pegmatites and in Veins Almost Never Brownish or Reddish.
Betafite (fresh)Uranium Columbate15-27Black to Greenish-BrownGlassy to Sub-Metallic4-54-5In Pegmatites; Less Commonly, in Placers. Commonly Altered to Brown and Yellow Green.
EuxeniteRare Earth Titarium Columbate1-20Black to Brown “Liver Brown”Glassy When Fresh5-74-6Nests or Pockets in Pegmatites.
SamarskiteRare Earth Columbate9-18Black to Brown “Liver Brown”Glassy When Fresh5-64-6Similar to Euxenite
Fergusonite (Fresh)Rare Earth Columbate0-8Black to Brown “Liver Brown”Glassy5-64-6In Pegmatites; Less Commonly, in Placers. Usually Externally Coated with Buff to Pinkish Clay-like Material.
Brannerite (Fresh)Uranium Titanium oxide40Jet Black (Brownish, Greenish)Brilliant44-5In Placers. Rare: Known to Occur in the United States only in Idaho. Alters to Yellowish-Brown.
ThucholiteHydrocarbon2-8Jet BlackBrilliant3-42Coal-Like: Will Burn. Sometimes Replaces Original Uraninite.
CarnotitePotassium Uranium Vanadate50-55Canary YellowEarthy or Pearly2-34+Scattered Irregular Lenses in Sandstone Beds. Frequently Associated With Fossil Logs or Bones.
TyuyamuniteCalcium Uranium Vanadate48-55Greenish YellowEarthy or Pearly2-33-4Associated With Calcite Minerals. Similar to Carnotite.
AutuniteCalcium Uranium Phosphate60

 

Lemon/Yellow or Apple GreenPearly2-33Mica-Like Crystals, Usually Small, Earthy. A Common Secondary Uranium Mineral
Pyrochlore-MicoliteColumbium Tantalum Oxide0-15Pale Yellow to Colorless and OthersGlassy or Resinous5-64-6In Pegmatites, Syenites, Some Limestones. Often Associated with Lithium or Fluorine Minerals Placers.
UranophaneCalcium Uranium Silicate65Various Shades of YellowPearly to Greasy2-34An alteration Product of Gummite, Pitchblende or Other Uranium Minerals. Commonly Associated With Other Secondary Uranium Minerals.
GummiteVariable40-80Yellow to Orange and VariableDull, Waxy, Greasy2-54-6Commonly Associated With Pitchblende. An Alteration Product of Uranium Minerals. Chiefly Uranium Oxide, Water and Lead.
Schroeck-IngeriteCarbonate and Sulphate Containing Uranium30Yellow to Greenish- YellowPearly2-31-2Rounded Masses Distributed in Gypsum-Bearing Sandy Clay.
Meta-Torbernite Also TorberniteCopper Uranium Phosphate60Various Shades of GreenPearly2-33-4Mica-Like Square Crystals. With Other Uranium Minerals as Coatings on Many Types of Rocks.

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