Carnotite
Specimen Origin: Montrose County (Colorado, USA)
In Montrose County, particularly within the benches of the Jurassic Morrison Formation, carnotite is found in sandstone beds of the Salt Wash Member. These sandstones are impregnated with uranium- and vanadium-bearing minerals, forming irregular ore bodies that historically ranged from small pockets to deposits containing tens of thousands of tons. The district was extensively mined during the early to mid-20th century for radium, uranium, and vanadium, and is well known for producing vivid yellow carnotite specimens of both scientific and economic importance.
Carnotite
Carnotite is a hydrated potassium uranium vanadate with the formula K₂(UO₂)₂(VO₄)₂·3H₂O. It forms bright yellow to greenish-yellow crusts, earthy aggregates, and microcrystalline coatings within oxidized sandstones. As a primary ore of both uranium and vanadium, it is moderately soft, strongly radioactive, and remains a historically significant mineral for its role in the nuclear and vanadium industries.
