Kingsmountite - Germany, Bavaria, Hagendorf-South Pegmatite - 0,6 mm high Photos from tomeikminerals.com can be used under a Creative Commons Licenese 4.0 CC-BY, as explained in: https://www.tomeikminerals.com/about-me . — Photo: Henk Smeets - Tomeik Minerals · CC BY 4.0
Kingsmountite
Kingsmountite is an IMA-recognized mineral species in the phosphate class, with the chemical formula Ca₃MnFe²⁺Al₄(PO₄)₆(OH)₄·12H₂O.
It crystallizes in the monoclinic crystal system (space group C2). It is a member of the Calcioferrite structural group.
Key properties: Mohs hardness 2.5; specific gravity 2.51; White streak; Pearly to fibrous luster; optically biaxial.
IMA symbol Kmo, IMA status: approved, named in 1978.
A secondary mineral formed from alteration of primary phosphates by descending oxidizing ground water in complex granite pegmatites.
It is found associated with Mitridatite, birnessite (Foote mine, North Carolina, USA); whitlockite, cyrilovite (Tip Top mine, South Dakota, USA); eosphorite, laueite, lun’okite.
The name refers to the town, KINGS MOUNTain, North Carolina, USA, near which the mineral was first collected.