Images
Formula:Ca(UO2)2(VO4)2.5-8H2O
Hydrated normal vanadate,
carnotite group
Crystal System: Orthorhombic
Specific gravity: 3.57 to 4.35 measured, 3.59 calculated
Hardness: 1½ to 2
Streak: Light yellow
Colour: Canary yellow, lemon-yellow; greenish yellow (upon exposure to sunlight); colourless to pale yellow in transmitted light
Solubility: Insoluble in dilute acetic acid; soluble in hydrochloric, nitric and sulphuric acids
RADIOACTIVE
Environments
Tyuyamunite is an uncommon secondary vanadate occurring in the oxidised zones
of uranium-vanadium deposits, especially those of the Colorado Plateau type (Mindat, Webmin, HOM). Associated minerals include
metatyuyamunite, carnotite,
corvusite, uranophane,
volborthite and gypsum
(HOM, Mindat).
Localities
At the type locality, the Tyuya-Muyun Cu-V-U deposit, Aravan District, Osh Region, Kyrgyzstan, tyuyamunite occurs in Carboniferous
limestone associated with turanite,
malachite, calcite and
baryte
(Mindat).
At the Cripple creek mining district, Colorado, USA, tyuyamunite has been reported associated with
fluorite, talc, kaolinite
and gypsum
(Minrec 36.2.182).
Alteration
Tyuyamunite easily dehydrates in a dry atmosphere to metatyuyamunite
(Mindat).
Back to Minerals