General Information:
Chemical Formula:
(Ca,Y)6(Al,Fe+++)Si4B4O20(OH)4
Composition:
(Molecular Weight = 915.92 gm)
Calcium 17.50 % Ca
Yttrium 19.41 % Y
Aluminum 2.21 % Al
Iron 1.52 % Fe
Silicon 12.27 % Si
Boron 4.72 % B
Hydrogen 0.44 % H
Oxygen 41.92 % O
Empirical Formula:
Ca4Y2Al0.75Fe3+0.25Si4B4O20(OH)4
Environment:
Pegmatite
IMA Status:
Approved IMA 1987
Locality:
Kragero, Telemark, norway.
Physical Properties:
Cleavage:
None
Color:
green yellow, grayish black, reddish brown, or black.
Density:
3.7
Diaphaniety:
Translucent to subtranslucent
Habits:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., ,
Hardness:
5.5 - Knife Blade
Luster:
Vitreous - Greasy
More details...