copper

Color	Reddish-brown, green (due to oxidation)
Luster	Metallic, sub-metallic
Hardness	2.5 - 3 on Mohs scale
Streak	Copper-red when pure
Specific Gravity	2.7 - 8.9 (depending on type)
Cleavage	None
Fracture	Jagged, uneven
Transparency	Opaque
Crystal System	Cubic (often massive)
Associated Minerals	Quartz, pyrite, calcite, iron oxides