General Information:
Chemical Formula:
Ca2Fe++(Fe+++,Al)2(SiO4)(Si2O7)(OH)2·(H2O)
Composition:
(Molecular Weight = 545.54 gm)
Calcium 14.69 % Ca
Aluminum 2.47 % Al
Iron 25.59 % Fe
Silicon 15.44 % Si
Hydrogen 0.74 % H
Oxygen 41.06 % O
Empirical Formula:
Ca2Fe2+Fe3+1.5Al0.5(SiO4)(Si2O7)(OH)2·(H2O)
IMA Status:
Approved IMA 1968
Name Origin:
Named in 1971 by Moore for Julian Royce Goldsmith (1918-), American geochemist, University of Chicago.
Physical Properties:
Color:
black, greenish black, or green.
Density:
3.602
Diaphaniety:
Translucent
Hardness:
4.5 - Between Fluorite and Apatite
Luster:
Sub Metallic
More details...