Nitscheite
Nitscheite is an IMA-recognized mineral species in the sulfate class, with the chemical formula (NH₄)₂[(UO₂)₂(SO₄)₃(H₂O)₂]·3H₂O.
It crystallizes in the monoclinic crystal system (space group P2_1/n).
Key properties: Mohs hardness 2; specific gravity 3.3; Very pale-yellow streak; Vitreous luster; optically biaxial.
IMA symbol Nih, IMA status: approved, named in 2021.
Secondary, in association with post-mining oxidation of asphaltum-rich sandstone beds laced with uraninite and sulfides in a damp underground environment.
It is found associated with Chinleite-(Y), gypsum, pyrite, Co-rich rietveldite.
The mineral was named to honor German/American nuclear chemist Heino Nitsche (1949-2014) for his work on nuclear and radiochemistry of heavy elements, nuclear forensics.