This is one of the rarest sulfosalts in the world. This specimen is a very rich, incredibly rare, superb quality, crystallized specimen of the triclinic lead, tin, iron, antimony sulfosalt Franckeite consisting of somewhat "sword"-shaped crystals oriented into spherical aggregates sitting on matrix! This piece is a great small cabinet specimen for somebody looking to own a rare and highly displayable mineral specimen. This species belongs to the only group of minerals that forms in naturally "round" or "cylindrical" shaped crystals. This specimen is over 30 years old and was part of the best find of the material. There were only a handful of good specimens, and well crystallized display pieces like this (especially on matrix) are few and far between.