Cuprite single crystal (natural) ( Cu2O ) Copper oxide

Crystal Properties
Crystal growth method	Natural
Crystal orientation	(001) (100) (110) (111) others on request
Maximum size	up to 10 x 10 mm, standard 4 x 4 mm
Crystallographic properties	a = 4,27 Å V 77.77 Å Z = 2
Crystallographic symmetry	cubic (4/m 3 2/m)
Crystal system	Cubic hexocathedral
Twinning structure	no, except natural defects
Mohs scale hardness	3.5 to 4
Diaphaneity	Transparent, translucent
Specific gravity	6.14 g/cm3
Colour	Dark red to conchineal red
Refractive index	n = 2.849
Pleochroism	Visible