VS
Name
—
Ba(Si,Al)₄(O,OH)₈·H₂O
Formula
—
Mineral Species
Entry type
—
Silicates
Chemical class
—
Monoclinic
Crystal system
—
2–3
Mohs hardness
—
3.413
Specific gravity
—
—
Streak
—
Vitreous to satiny
Luster
—
Perfect on {001}, imperfect on {110}
Cleavage
—
P2_1
Space group
—
—
Structural group
—
Cym · Grandfathered
IMA
—
1949
Named in
—
Colorless when pure; commonly dark green or brown due to inclusions of alteration products
Typical colors
—
Ba · Si · Al · O · H
Elements
—