Kunatite
Kunatite is an IMA-recognized mineral species in the phosphate class, with the chemical formula CuFe³⁺₂(PO₄)₂(OH)₂·4H₂O.
It crystallizes in the monoclinic crystal system (space group P2_1/c). It is a member of the Arthurite structural group.
Key properties: Mohs hardness 3; specific gravity 3.063; Pale yellow streak; Silky (aggregates) luster; optically biaxial.
IMA symbol Kun, IMA status: approved, named in 2007.
Secondary along fractures and in vugs deposited from circulating groundwaters charged with P, U and Cu that were derived from oxidation of primary fluorapatite in granite.
It is found associated with Chalcosiderite-turquoise, libethenite, pseudomalachite (Lake Boga); isokite, triplite, chalcosiderite-turquoise, leucophosphite, pharmacosiderite, whitmoreite.
The name comes from the Australian aboriginal words kunat kunat, meaning 'cotton weed’, a species that grows in the region around Lake Boga where studied samples were collected.