General Information:
Chemical Formula:
CaAl2Si7O18·7(H2O)
Composition:
(Molecular Weight = 704.74 gm)
Calcium 5.69 % Ca
Aluminum 7.66 % Al
Silicon 27.90 % Si
Hydrogen 2.00 % H
Oxygen 56.76 % O
Empirical Formula:
CaAl2Si7O18·7(H2O)
Environment:
Found in diabase-tuff from the Komandor islands, Bering Sea and other diabase rocks world wide.
IMA Status:
Approved IMA
Locality:
Copper Isand, Commander Islands, Bering Sea.
Name Origin:
Named after Georg Wilhelm Steller (1709-1746), German explorer, zoologist and the discoverer of the Komandor Islands.
Physical Properties:
Cleavage:
[010] Perfect, [100] Imperfect, [001] Imperfect
Color:
white, pink, salmon orange, brown, or red.
Density:
2.12 - 2.13, Average = 2.12
Diaphaniety:
Transparent to translucent
Habits:
Stellate - Occurs as spherical, radial aggregates radiating from a "star" like point., Tabular - Form dimensions are thin in one direction., Spherical - Spherical, rounded aggregates.
Hardness:
4.5 - Between Fluorite and Apatite
Luminescence:
Non-fluorescent.
Luster:
Vitreous (Glassy)
Streak:
white
More details...