Antlerite
Mineral Cu3(SO4)(OH)4
About it
Nearly identical to brochantite by eye and needs testing to separate; it favours drier, more acidic ore zones. Was once the main copper ore at Chuquicamata in Chile; named for the Antler mine in Arizona.
- Type
- Mineral
- Group
- Sulfate, basic copper sulfate
- Formula
- Cu3(SO4)(OH)4
- Hardness (Mohs)
- 3.5–4
- Specific gravity
- 3.88–3.95
- Streak
- pale green
- Lustre
- vitreous (glassy)
- Crystal system
- Orthorhombic
- Colours
- emerald green, blackish green, light green
- Transparency
- transparent, translucent
- Cleavage and fracture
- perfect in one direction
Typical values: real specimens vary. For more, see mindat.org.