Letovicite

Letovicite (/lɛtoʊˈvɪsaɪt/) is an ammonium sulfate mineral with composition (NH₄)₃H(SO₄)₂ (IUPAC: triammonium sulfate hydrogensulfate, Nickel–Strunz classification 07.AD.20).

It is a rare colorless or white monoclinic secondary mineral formed during the burning of waste coal heaps and as a deposit in hot springs. It was first described from the Letovice region of Moravia in 1932.

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