Image: Andrew Silver (Public domain)
orthorhombicuncommonSulfosalts
Bournonite
PbCuSbS₃
The image displays a dark, metallic, lead-gray to black specimen of Bournonite, likely showing its characteristic blocky or tabular crystal forms.
Bournonite Physical Properties
Mohs Hardness
2.5Crystal System
orthorhombicLuster
metallicStreak Color
steel gray to blackCleavage
distinct on {010}, poor on {001} and {110}Fracture
unevenSpecific Gravity
5.8Colors
steel-gray, lead-gray, iron-blackTransparency
opaqueType Locality
Cornwall (England), Harz Mountains (Germany), Potosí (Bolivia)Mineral Group
SulfosaltsUses
minor ore of lead, minor ore of copper, minor ore of antimony, collectorAssociated Minerals
galena, sphalerite, tetrahedrite, chalcopyrite, pyrite, quartzRarity
uncommonGeological Context
Bournonite typically forms in hydrothermal veins, often in association with other lead, copper, and antimony sulfides and sulfosalts, under moderate to low-temperature conditions.
