Stilpnomelane group

Stilpnomelane is a phyllosilicate mineral. It has the chemical formula .

Franklinphilite is a phyllosilicate of the stilpnomelane group. Known from only two localities (with a third unconfirmed locality in Switzerland) It was found exclusively from the Franklin and Sterling Hill mines in Franklin, Sussex County, New Jersey. until 2013, when a locality in Wales was confirmed