VS
Name
—
Mg₂Fe³⁺O₂(BO₃)
Formula
—
Mineral Species
Entry type
—
Borates
Chemical class
—
Monoclinic
Crystal system
—
6
Mohs hardness
—
4.18
Specific gravity
—
Dark brown
Streak
—
Submetallic
Luster
—
—
Cleavage
—
P2/m
Space group
—
Hulsite
Structural group
—
Mhul · Approved
IMA
—
1983
Named in
—
Black; bluish gray to grayish white in reflected light
Typical colors
—
Mg · Fe · O · B
Elements
—