General Information:
Chemical Formula:
Mg2Al4Si5O18
Composition:
(Molecular Weight = 584.95 gm)
Magnesium 8.31 % Mg
Aluminum 18.45 % Al
Silicon 24.01 % Si
Oxygen 49.23 % O
Empirical Formula:
Mg2Al4Si5O18
Environment:
Magmatic, metamorphic, and pegmatitic rocks.
Locality:
Bodenmais, Germany.
Name Origin:
From the French mining engineer and geologist P. L. A. Cordier (1777-1861).
Physical Properties:
Cleavage:
[010] Poor
Color:
colorless, pale blue, violet, yellow, or gray.
Density:
2.55 - 2.75, Average = 2.65
Diaphaniety:
Transparent to translucent
Habits:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Massive - Granular - Common texture observed in granite and other igneous rock.,
Hardness:
7 - Quartz
Luminescence:
None.
Luster:
Vitreous (Glassy)
Streak:
white
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