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Coffinita

Coffinita is a mineral with formula USiO₄, in the Silicatos group. This specimen comes from Temple Mountain, San Rafael, Emery County, Utah, Estados Unidos.

Coffinita from Temple Mountain, San Rafael, Emery County, Utah, Estados Unidos — Terrium

Description

Black to dark grey, micaceous, lustrous masses dispersed in silicified matrix. Compact appearance with metallic reflections and fine surface glints. Measured radioactivity 0.60 µSv/h.

History of this specimen

This piece is a direct child of the nuclear boom on the Colorado Plateau in the 1950s–1960s. It was the so‑called "uranium fever", supported by the US government buying at favourable prices, when thousands went into the desert with Geiger counters in hand discovering new species. I keep it with its original and handwritten labels, which show a demonstrable chain of custody: originally documented by Professor Frank Bauer and, in the 1980s, in the personal collection of Dr G. Jung.

About Coffinita

An apparently simple uranium silicate, but in fact extremely rare. Isostructural with zircon, it is usually a product of uraninite alteration. It typically occurs massive or intermixed with organic matter (such as radioactive petrified wood), only rarely with visible crystal habit. It was described in 1954, at the height of the uranium boom.

About the locality

Temple Mountain is a classic Triassic sandstone uranium deposit within the San Rafael district, Utah. Known since the mid-20th century, it yielded specimens of uraninite, autunite and coffinite—minerals that marked the start of the United States uranium boom.

Technical data

Catalogue No.
0170
Composition
USiO₄
Name
Coffinita
Group
Silicatos
Category
Núcleus Ardens
Matrix
Matriz silicificada con impregnaciones negras
Mine
Temple Mountain
District / Municipality
San Rafael
Province
Emery County
Region
Utah
Country
Estados Unidos
Size (cm)
4.5 x 2.5 x 1.5
Weight
13 g
Ex-collection
Prof. Frank Bauer > Dr. G. Jung
Etymology
Named in honour of R. B. Coffin, a US Geological Survey geologist.
Quality
Muy buena
Value trend
Estable

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