TERRIUM — A mineralogy cabinet


Tyuyamunita

Tyuyamunita is a mineral with formula Ca(UO₂)₂(VO₄)₂·5–8H₂O, in the Fosfatos (uranovanadatos) group. This specimen comes from Butler #2 Mine, Crescent Creek, Garfield County, Utah, Estados Unidos and joined the Terrium collection in 2025.

Tyuyamunita from Butler #2 Mine, Crescent Creek, Garfield County, Utah, Estados Unidos — Terrium

Description

Intense yellow crystalline aggregates in rosettes covering 2/3 of the matrix, with strong contrast against the reddish-brown background. Richer coverage than many tyuyamunite specimens. Registers peaks of 0.80 µSv/h.

About Tyuyamunita

Calcium uranyl vanadate, i.e. a member of the autunite group in which vanadium replaces phosphorus. It is a neoformation mineral: it forms in the oxidation zone and can develop even in relatively recent historic mines. Minerals of this group have been recorded on dumps or in galleries within less than a century, sometimes in only a few decades; they rarely take more than a few thousand years.

About the locality

Butler #2 Mine, Utah, is known for its brightly coloured uranyl vanadates. The arid environment and surficial alteration of uranium minerals favoured the formation of crusts of tyuyamunite and carnotite—classics of United States mineralogy.

Technical data

Catalogue No.
0172
Composition
Ca(UO₂)₂(VO₄)₂·5–8H₂O
Name
Tyuyamunita
Group
Fosfatos (uranovanadatos)
Category
Núcleus Ardens
Matrix
Limonítica
Associations
carnotita
Mine
Butler #2 Mine
District / Municipality
Crescent Creek
Province
Garfield County
Region
Utah
Country
Estados Unidos
Size (cm)
3.7 x 2.1 x 0.7
Weight
8.2 g
Acquired
2025
Etymology
The name honours the Russian geologist V. I. Tyuyamun, in whose region of Uzbekistan it was first described.
Quality
Muy buena
Value trend
Al alza

Related specimens

← Back to Terrium catalogue