VS
Name
—
Ca₂(Fe²⁺₄Al)(Si₇Al)O₂₂(OH)₂
Formula
—
Mineral Species
Entry type
—
Silicates
Chemical class
—
Monoclinic
Crystal system
—
5–6
Mohs hardness
—
3.12–3.3
Specific gravity
—
white
Streak
—
[Vitreous.]
Luster
—
Perfect on {110}, with intersections at 56± and 124±; may show partings on {100}, {010}
Cleavage
—
C2/m
Space group
—
Amphibole
Structural group
—
Fhbl · Approved
IMA
—
1978
Named in
—
Black, Green
Typical colors
—
Ca · Fe · Al · Si · O · H
Elements
—