VS
Name
—
Cu₃₁S₁₆
Formula
—
Mineral Species
Entry type
—
Sulfides
Chemical class
—
Monoclinic
Crystal system
—
2.5–3
Mohs hardness
—
5.749
Specific gravity
—
—
Streak
—
Metallic. Anisotropism: Weak. R1 –R2: (400) 36.1–37.3, (420) 36.2–37.1, (440) 36.0–36.8, (460) 35.7–36.4
Luster
—
—
Cleavage
—
P2_1/n
Space group
—
—
Structural group
—
Dju · Approved
IMA
—
1962
Named in
—
Black; gray in reflected light
Typical colors
—
Cu · S
Elements
—