VS
Name
—
Mn²⁺₅Fe³⁺(Si₃Fe³⁺O₁₀)(OH)₈
Formula
—
Mineral Species
Entry type
—
Silicates
Chemical class
—
Orthorhombic
Crystal system
—
2.5
Mohs hardness
—
3.01
Specific gravity
—
—
Streak
—
—
Luster
—
{001}, perfect
Cleavage
—
—
Space group
—
Chlorite, Clay
Structural group
—
Gye · Grandfathered
IMA
—
1955
Named in
—
Deep brown with reddish internal reflections, light chocolate-brown; in transmitted light, pale to dark brown
Typical colors
—
Mn · Fe · Si · O · H
Elements
—