Berryite
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Berryite is a mineral with the formula Pb35Bi7S16. It occurs as gray to blue-gray monoclinic prisms. It is opaque and has a metallic luster. It has a Mohs hardness of 3.5 and a specific gravity of 6.7
Black acicular crystals of the rare Pb-Ag sulfide from a Colorado locality: Mike Mine, San Juan County, Colorado, United States
Cryolite
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Cryolite is a rare mineral identified with the once-large deposit at Ivittuut on the southwest coast of Greenland, mined commercially until 1987.
Cryolite from Ivittuut, Greenland
Peter Christian Abildgaard
The cryolite mine at Ivigtut, Greenland, summer 1940