VS
Name
—
Mn²⁺Mn³⁺₆O₈(SiO₄)
Formula
—
Mineral Species
Entry type
—
Silicates
Chemical class
—
Tetragonal
Crystal system
—
6–6.5
Mohs hardness
—
4.72–4.83
Specific gravity
—
Brownish black to steel-gray
Streak
—
Submetallic. Anisotropism: Weak in air to distinct in oil, dark to lighter slate gray. R1 {R2: (400) 23.4–25.4
Luster
—
Perfect on {112}
Cleavage
—
I4_1/acd
Space group
—
Braunite
Structural group
—
Bnt · Grandfathered
IMA
—
1828
Named in
—
Brown, Black
Typical colors
—
Mn · O · Si
Elements
—