Graftonite
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Graftonite is an iron(II), manganese, calcium phosphate mineral with formula: (Fe++,Mn,Ca)3(PO4)2. It forms lamellar to granular translucent brown to red-brown to pink monoclinic - prismatic crystals. It is vitreous with a Mohs hardness of 5 and a specific gravity of 3.67 to 3.7.
It was first described from its type locality of Melvin Mountain, Grafton, Grafton County, New Hampshire.