General Information:
Chemical Formula:
Al16B6Si2O27
Composition:
(Molecular Weight = 1,144.71 gm)
Aluminum 37.71 % Al
Silicon 4.91 % Si
Boron 5.67 % B
Oxygen 51.71 % O
Empirical Formula:
Al16B6Si2O37
Environment:
Found in a tourmaline - quartz intergrowth in granitic pegmatite cutting granulite-facies metapelitic rocks, Structurally related to sillimanite.
IMA Status:
Approved IMA (Dana # Added)
Locality:
Stornes Peninsula, Larsemann Hills, Prydz Bay, east Antarctica. Almgjotheii in the aureole of the Rogaland intrusive complex, southwestern Norway.
Name Origin:
Named after its composition of (bo)ron, (al)uminum, and (sil)icon.
Physical Properties:
Cleavage:
[???] Fair, [???] Fair
Color:
white or colorless.
Density:
3.06
Diaphaniety:
Transparent
Habits:
Fibrous - Crystals made up of fibers., Aggregates - Made of numerous individual crystals or clusters.,
Luster:
Vitreous (Glassy)
Streak:
white
More details...