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Uranocircita

Uranocircita is a mineral with formula Ba(UO₂)₂(PO₄)₂·10H₂O, in the Fosfatos group. This specimen comes from Mina Diéresis, El Cabril (Hornachuelos), Córdoba, Andalucía, España.

Uranocircita from Mina Diéresis, El Cabril (Hornachuelos), Córdoba, Andalucía, España — Terrium

Description

Uranocircite flakes and impregnations forming small yellowish-green plates scattered across the feldspar (orthoclase) matrix. 11,50 µSv/h

History of this specimen

This is, demonstrably, the first radioactive specimen acquired by the great collector Carlos Prieto Paramio, as recorded on his own handwritten label. He bought it in the 1940s from Adela Ávila, at the Espasa-Calpe shop on Calle Barquillo in Madrid. The date is absolutely exceptional: it belongs to the decade when uranium went from a mineralogical curiosity to a strategic material, amid Hiroshima, Nagasaki and the dawn of the nuclear age. Curiously, Prieto Paramio did not record the exact year of purchase, but did remember the name of the person who sold it to him. Although he identified the specimen as autunite at the time, it is now recognised as uranocircite.

About Uranocircita

NEOFORMATION. Uranocircite is a hydrated barium uranyl phosphate of the autunite group. It typically shows a yellow-green colour, lamellar or tabular habit and strong fluorescence. It forms as a secondary mineral in the oxidation zones of uranium deposits and may be visually confused with autunite when analytical data or precise provenance are lacking.

About the locality

In the 1940s, Franco’s government took control of the uranium deposits of Sierra Albarrana and El Cabril, removing Antonio Carbonell, who until then had explored, promoted and managed the area. Mina Diéresis belongs to this district, and this specimen dates precisely from that transitional period, when uranium ceased to be treated as a mining curiosity and became a strategic resource of the State.

Technical data

Catalogue No.
0695
Composition
Ba(UO₂)₂(PO₄)₂·10H₂O
Name
Uranocircita
Group
Fosfatos
Category
Núcleus Ardens
Matrix
Ortoclasa
Mine
Mina Diéresis
District / Municipality
El Cabril (Hornachuelos)
Province
Córdoba
Region
Andalucía
Country
España
Size (cm)
5 x 3 x 2.5
Weight
14.2 g
Ex-collection
Carlos Prieto Paramio
Etymology
From German «Uranocircit», a name formed from uranium and a root historically associated with the species' characteristic yellow colour.
Quality
Notable
Value trend
Al alza

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