VS
Name
—
Bi₇Te₃
Formula
—
Mineral Species
Entry type
—
Sulfides
Chemical class
—
Hexagonal
Crystal system
—
2
Mohs hardness
—
8.81–8.91
Specific gravity
—
—
Streak
—
Metallic. Anisotropism: Slight, pale gray to dark gray. R1 –R2: (400) 59.0–61.8, (420) 59.3–62.5, (440) 59.9–63.3
Luster
—
Perfect on {0001}, warped
Cleavage
—
—
Space group
—
Tetradymite
Structural group
—
Hdl · Grandfathered
IMA
—
1945
Named in
—
Tin-white, tarnishing iron-black; in polished section, white, between that of galena and silver
Typical colors
—
Bi · Te
Elements
—