Falsterite
Falsterite is a rare phosphate mineral with the formula Ca2MgMn2+24Zn48414. It is a pegmatitic mineral, related to the currently approved mineral ferraioloite.Falsterite was found in Palermo No. 1 pegmatite, North Groton, Grafton County, New Hampshire, US. Co-type locality is pegmatite at Estes quarry, Baldwin, Cumberland County, Maine, US. Falsterite is a product of alteration of triphylite and sphalerite.Crystal structure
Main features of the crystal structure of falsterite, which is somewhat similar to that of schoonerite, are:
- chains of Fen+O6 octahedra, displaying edge-sharing
- chains of ZnO4 tetrahedra, that display corner-sharing
- sheets, parallel to, formed by linking the above two types of chains by PO4 tetrahedra
- slabs formed by linking the sheets with MnO6 octahedra and CaO7 polyhedra
The slabs are bridged by dimers of MgO6 octahedra that display edge-sharing. Magnesium-bearing octahedra share edges with zinc-bearing tetrahedra.
