VS
Name
—
KCa₂(Fe²⁺₄Fe³⁺)(Si₆Al₂)O₂₂(OH)₂
Formula
—
Mineral Species
Entry type
—
Silicates
Chemical class
—
Monoclinic
Crystal system
—
5.5
Mohs hardness
—
3.51
Specific gravity
—
Dark green
Streak
—
Vitreous
Luster
—
Perfect on {110}
Cleavage
—
C2/m
Space group
—
Amphibole
Structural group
—
Phst · Approved
IMA
—
2019
Named in
—
Black
Typical colors
—
K · Ca · Fe · Si · Al · O · H
Elements
—