Category Oxide minerals Crystal system Orthorhombic | Strunz classification 4.JJ.10 Space group P21nm | |
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Formula
(repeating unit) Ba(UO2)3(SeO3)2(OH)4•3H2O Crystal class Pyramidal (mm2)
(same H-M symbol) | ||
Guilleminite (Ba(UO2)3(SeO3)2(OH)4•3H2O) is a uranium mineral named by R. Pierrot, J. Toussaint, and T. Verbeek in 1965 in honor of Jean Claude Guillemin (1923–1994), a chemist and mineralogist. It is a rare uranium/selenium mineral found at the Musonoi Mine in the Katanga Province of the Democratic Republic of the Congo.
This secondary mineral also includes barium in its structure, in addition to selenium and uranium. It is bright yellow in colour and usually has an acicular crystal habit. It has a Mohs hardness of 2–3.
References
Guilleminite Wikipedia(Text) CC BY-SA