:Locality: Jomac Mine, San Juan County, Utah, United States of America Size: 5 × 3.5 × 1.4 cm Description: On a sandstone matrix some yellow crusts of coconinoite formed by small tabular to micaceous crystals. This sample has been analyzed by SEM-EDS. — Photo: Joan Rosell , from rosellminerals.com · CC BY-SA 4.0
Coconinoite
A uranyl phosphate uranium ore discovered in Coconino County, Arizona.
Intro adapted from Wikipedia (CC BY-SA).
Coconinoite is an IMA-recognized mineral species in the phosphate class, with the chemical formula Fe³⁺₂Al₂(UO₂)₂(PO₄)₄(SO₄)(OH)₂·20H₂O.
It crystallizes in the monoclinic crystal system.
Key properties: optically biaxial.
IMA symbol Coc, IMA status: approved, named in 1965.
Found in the oxidized zone of vanadium-poor Colorado Plateau-type U- V deposits (Utah and Arizona, USA).
It is found associated with Gypsum, jarosite, "limonite", quartz, clay minerals, coalized wood (Jomac mine, Utah, USA).
The name refers to Coconino Co., Arizona, USA, from which samples were obtained. Type Material: National Museum of Natural History, Washington, D.C., USA, 119772.