Uramarsite
Uramarsite is an IMA-recognized mineral species in the arsenate class, with the chemical formula (NH₄)(UO₂)(AsO₄)·3H₂O.
It crystallizes in the triclinic crystal system (space group P1). It is a member of the Meta-autunite structural group.
Key properties: Mohs hardness 2.5; specific gravity 3.22; White streak; Vitreous. Fluoresces green in UV luster.
IMA symbol Uaa, IMA status: approved, named in 2005.
Found in the oxidized zone of pitchblende-sulfide mineralization in highly-fractured, hydrothermally-altered felsite porphyry and tuff breccia.
It is found associated with Calcite, arsenopyrite, pyrite, galena, chistyakovaite, natrouranospinite, scorodite, arseniosiderite, mansfieldite, metazeunerite, trögerite.
An acronym for the major chemical components URanium, AMmonium, ARSenate.