Bournonite
Mineral PbCuSbS3
Also called Cogwheel ore, Wheel ore, and Endellione
Take care.
- Contains lead: Wash your hands after handling it, keep it away from children, and don't make dust.
- Toxic: Wash your hands after handling it, don't lick or taste it, and don't make dust.
About it
Steel grey crystals, often twinned into cogwheel shapes. Classic from Herodsfoot in Cornwall, Neudorf in the Harz, Germany, and Yaogangxian, China.
- Type
- Mineral
- Group
- Sulfosalt, bournonite group
- Formula
- PbCuSbS3
- Hardness (Mohs)
- 2.5–3
- Specific gravity
- 5.7–5.9
- Streak
- steel grey to black
- Lustre
- metallic
- Crystal system
- Orthorhombic
- Colours
- steel grey, blackish lead grey
- Transparency
- opaque
- Cleavage and fracture
- imperfect; subconchoidal to uneven fracture
Typical values: real specimens vary. For more, see mindat.org.