VS
Name
—
AlAl₆BSi₃O₁₈
Formula
—
Mineral Species
Entry type
—
Silicates
Chemical class
—
Orthorhombic
Crystal system
—
7–8.4
Mohs hardness
—
3.21–3.41
Specific gravity
—
white
Streak
—
Vitreous to dull
Luster
—
Distinct on {100}, poor on {110}; parting on {001}
Cleavage
—
Pmcn
Space group
—
Dumortierite
Structural group
—
Dum · Approved
IMA
—
1881
Named in
—
Blue, Purple, Pink, Brown
Typical colors
—
Al · B · Si · O
Elements
—