Carnotite
Species
Uncommon · K₂(UO₂)₂(VO₄)₂·3H₂O
Potassium uranyl vanadate, a bright canary yellow powder that colours the sandstones of the Colorado Plateau, often around petrified logs; one per cent is enough to turn the rock yellow. Before the first nuclear reactor of 1942 it was mined mainly for radium or vanadium, then as a major uranium ore. Radioactive.
Identity
- Formula
- K₂(UO₂)₂(VO₄)₂·3H₂O
- Chemical class
- Phosphate
- Ore of
- Vanadium
Crystallography
- Crystal system
- Monoclinic
- Habits
- Earthy, Tabular, Massive
- Fracture
- Uneven
Physical properties
- Mohs hardness
- 2
- Density
- 4.7 g/cm³
- Luster
- Dull, Earthy, Silky
- Colors
- yellow, greenish yellow
- Streak
- yellow
- Transparency
- Translucent
Geology
- Origins
- Sedimentary
- Host rocks
- Sandstone, shale and clay
- Associated minerals
- Gypsum, Barite
- Geography
- USA (Uravan and Paradox Valley, Colorado; Monument Valley, Arizona; Utah), Australia (Radium Hill; Yeelirrie), Kyrgyzstan (Tyuya-Muyun)
Classification
- Rarity
- Uncommon
- Gem quality
- No
Sources
- M. Pasero and others, IMA Commission on New Minerals, Nomenclature and Classification, The New IMA List of Minerals, updated September 2026. International Mineralogical Association (CNMNC), 2026.
- J. W. Anthony, R. A. Bideaux, K. W. Bladh, M. C. Nichols, Carnotite. Mineral Data Publishing, Handbook of Mineralogy, 2001.
- Carnotite. Wikipedia.
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