General Information:
Chemical Formula:
Ca2(Al,Mn,Fe)3(SiO4)3(OH) = Ca2(Mn,Fe)Al2(SiO4)(Si2O7)O(OH)
Composition:
(Molecular Weight = 488.18 gm)
Calcium 16.42 % Ca
Manganese 10.13 % Mn
Aluminum 9.95 % Al
Iron 3.43 % Fe
Silicon 17.26 % Si
Hydrogen 0.21 % H
Oxygen 42.61 % O
Empirical Formula:
Ca2Al1.8Mn2+0.9Fe2+0.3(SiO4)3(OH)
Environment:
Contact metamorphic rocks.
Locality:
Piedmont, Italy.
Name Origin:
Named after its locality.
Physical Properties:
Cleavage:
[001] Good, [100] Distinct
Color:
yellow, carmine red, red, reddish brown, or reddish black.
Density:
3.4
Diaphaniety:
Translucent
Habits:
Blocky - Crystal shape tends to be equant (e.g. feldspars)., Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Massive - Granular - Common texture observed in granit e and other igneous rock.
Hardness:
6-7 - Orthoclase-Quartz
Luminescence:
Non-fluorescent.
Luster:
Vitreous (Glassy)
Streak:
red
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