Powellite, Molybdenite
Holts Ledge, Lyme, Grafton County, New Hampshire, USA
Powellite pseudomorph after molybdenite. Hexagonal, platy molybdenite crystals degrading into powellite, in most cases leaving just a cast, like for the crystal on the top right. In some cases, the substitution is only partial, like for the crystal on the top left, where some black, metallic molybdenite is still visible. The powellite has a strong ...
© Simone Conti