Copper

Physical Properties
Chemical formula Cu
Class Native element
Crystal system Cubic
Habit Cubic
Octahedral
Dodecahedral
Crystals are usually malformed,
dendritic, arborescent, or in
irregular plates, scales,
or masses.
Color Copper-red
Rose-red
Hardness 2.5 to 3
Specific gravity 8.7 to 8.9
Cleavage None
Fracture Hackly
Luster Metallic
Transparency Opaque
Streak Copper-red
Twinning Contact
Penetration
after Perkins, 353-354

Copper in Hand Sample

Native copper

Native copper in Catoctin Fm. metabasalt

Further Reading

Copper at webmineral.com

Copper at mindat.org