TERRIUM — A mineralogy cabinet


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 and joined the Terrium collection in 1990.

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

Description

Yellowish uranocircite crusts on pale orthoclase matrix; pearly to vitreous lustre and intense green fluorescence under long‑wave UV. Under a UV torch, a multitude of minute reactive points is evident.

About Uranocircita

Secondary mineral. A hydrated barium uranyl phosphate. It belongs to the autunite group and, together with autunite (Ca) and torbernite (Cu), forms its principal phosphate triad: A(UO₂)₂(PO₄)₂·nH₂O. One of the formerly so‑called "uranium micas" owing to its platy‑tabular habit. It forms in the oxidised zones of uranium deposits.

About the locality

One of the great Spanish focal points of radium expectations in the 20th century. The engineer from Córdoba, Antonio Carbonell, had spent decades studying the pegmatites and rare minerals of northern Córdob and had been publishing on radioactive substances since at least 1916. By 1940 he had already documented uranium, radium, beryllium, and other strategic minerals in the area, as well as pointing out thousands of other possible locations. He founded «Berilo y Radio Español» and turned the enclave into a promising mining site. That fever transformed the territory: first, precarious settlements appeared, with adobe huts and brushwood roofs, but later, villages like Santa Bárbara emerged, with 46 houses, running water, electricity, bathrooms, and permanent medical services, something exceptional for the time. In 1945, after the atomic bombs, the Francoist state declared radioactive deposits strategic, sidelined Carbonell, and took control. Carbonell died two years later. Then the decline came with the realization that uranium did not form large continuous veins, but rather scattered, expensive, and unproductive pockets, leaving the villages almost empty. In 1961, the Nuclear Energy Board silently began introducing radioactive waste into the inactive Beta Mine. This nuclear cemetery remained secret until 1976, when two Cordoban journalists bravely exposed it in the article «Andalucía, vertedero atómico». They denounced using an impoverished region for those purposes, as well as exposing a total lack of safety measures symbolized by a «Danger: Radioactivity» rusted sign left abandoned on a pile of firewood. In 1986, ENRESA took over El Cabril, reconditioned the old village, and directed the emptying of the mine and the launch of the modern storage system. Today, the site no longer produces minerals, but it retains a paradox difficult to match: it was a failed mine, a nuclear cemetery, and yes the origin of some of the best known brannerites.

Technical data

Catalogue No.
0120
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)
4.8 x 4.5 x 2
Weight
47.2 g
Acquired
1990
Etymology
From the Greek "oura" (tail, referring to uranium) and "kirchos" (phalange), after the elongate morphology of some crystals (IMA 1922).
Quality
Buena
Value trend
Estable

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