VS
Name
—
K₂NaMn²⁺₇Ti₂(Si₄O₁₂)₂O₂(OH)₄F
Formula
—
Mineral Species
Entry type
—
Silicates
Chemical class
—
Triclinic
Crystal system
—
3–4
Mohs hardness
—
3.2–3.36
Specific gravity
—
Brown
Streak
—
Vitreous
Luster
—
Perfect on {100}
Cleavage
—
P-1
Space group
—
Astrophyllite-Kupletskite
Structural group
—
Kpt · Grandfathered
IMA
—
1956
Named in
—
Bright straw-yellow when fresh, dark brown to black when altered to manganese oxides
Typical colors
—
K · Na · Mn · Ti · Si · O · H · F
Elements
—