Graftonite

Graftonite
Graftonite with Triphylite Iron manganese calcium phosphate Palermo Mine, North Groton, New Hampshire
General
CategoryPhosphate minerals
Formula
(repeating unit)
(Fe2+,Mn,Ca)3(PO4)2
Strunz classification8.AB.20
Crystal systemMonoclinic
Crystal classPrismatic (2/m)
(same H-M symbol)
Space groupP21/c

Graftonite is an iron(II), manganese, calcium phosphate mineral with the chemical formula (Fe2+,Mn,Ca)3(PO4)2. It forms lamellar to granular translucent brown to red-brown to pink monoclinic prismatic crystals. It has a vitreous luster 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 in the town of Grafton, in Grafton County, New Hampshire.

References