Native bismuth seldom crystallizes so richly as you have here; an almost 2cm-thick seam of native bismuth crystals is layered between crude quartz "vein boundaries" within this natural matrix piece, which shows clearly how the bismuth crystallized to fill a thin fracture filling as it formed out of solution tens of millions of years ago (or more). The bismuth crystals exhibit metallic luster and dark gray color and reach 1 cm in length. Bismuth is a pure element here as crystals that are simply metal, and this material was long considered the best ore for smelting which resulted in few good (and heavy) specimens being saved until more modern times. Schema is a noted locality, and these have been mined here since the 1800s, through Soviet times. The crystal sprays sort of "erupt" upwards and contrast to the surrounding matrix, so it really displays well, for such a large bismuth specimen, as most are rather clunky and uniformly gray and without contrast. Massive at 558 grams. Ex Dr. Wouter van Tichelen collection.