Bismuth

Formula: Bi native element
Specific gravity: 9.7 - 9.8
Hardness: 2 to 2½
Streak: Lead grey
Colour: Silver white
Solubility: Slightly soluble in hydrochloric acid, readily soluble in sulphuric and nitric acid
Environments:

Pegmatites
Hydrothermal environments

Bismuth occurs in pegmatites and as an unaltered primary mineral in hypothermal, (high temperature) tin ore veins.

Common impurities: Fe,Te,As,S,Sb