Potosiite (rare sulfosalt)

Item Description

Potosiite is a very rare tin-poor variety of the rare sulfosalt franckeite. This rich, large piece is from the great find of 2004. Lustrous, metallic-gray blades to about 4 mm totally cover the large matrix. For those of you who are unaware, the crystals of potosiite on this specimen are VERY LARGE. Before these new specimens were discovered, some of the largest known crystals of potosiite were massive, uncrystallized, granules less than 1 mm in most cases. The crystals on this specimen are NOT micros, you can clearly see them with the naked eye and they are very distinct. These are undoubtedly some of the LARGER KNOWN POTOSIITE CRYSTALS IN EXISTENCE. Valued at $1000 for very large size and richness..