monoclinic
Moonstone
KAlSi3O8
Quick Facts
Hardness
6.0
Specific Gravity
2.56
Refractive Index
1.518
Crystal Structure
monoclinic[2/m]:{010}@1.0 + {110}@0.8 + {001}@0.7 + {100}@0.5 monoclinic
2/m
{010} {110} {001} {100}
Physical Properties
Crystal Systemmonoclinic
Hardness (Mohs)6.0
Specific Gravity2.56
CleavagePerfect in two directions at ~90 degrees
FractureUneven to conchoidal
LustreVitreous to pearly
Optical Properties
Refractive Index1.518
Birefringence0.005-0.008
PleochroismNone to weak
Dispersion0.012
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Open in Playground monoclinic[2/m]:{010}@1.0 + {110}@0.8 + {001}@0.7 + {100}@0.5 Related Minerals
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