Clearly, this complete alluvial nugget of native bismuth has one of the highest specific gravities of any metallic element. The weight is really shocking...bismuth is HEAVY stuff! This little rock masses over 1100 grams, about 3 pounds! It actually hurt my wrist to lift it, not thinking it would weigh so much and twisting as a result. The luster is bright with a gray color that has a slight tinge of iridescence. It is exceedingly rare to see alluvial bismuth in this size of a nugget, and in good condition.