This is a newly named, extremely rare mineral from Madagascar. Embedded in quartz are crystals of sub-metallic, taupe-gray, crystals to 2 cm in length. I obtained this in exchange from Dr. Pezzotta, who specializes in the minerals of Madagascar and I think could be safely considered the authority on finely crystallized rarities here...he told me these are among the largest fine crystals known for the species. I certainly have seen nothing comprable on the market, and for that matter you don't see much of it at all on the market.