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 hexoctahedral

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