monoclinic Inosilicates
Actinolite (Prismatic)
Ca2(Mg,Fe)5Si8O22(OH)2
Crystal Structure
#! Species: Actinolite
#! System: Monoclinic (2/m)
#! Habit: Elongated prismatic
monoclinic[2/m]:{110}@1.0 + {010}@0.8 + {100}@0.4 + {001}@0.9 | elongate(c:3.0)
monoclinic
2/m
{110} {010} {100} {001}
Quick Facts
Hardness
5.0
Specific Gravity
3.0
Refractive Index
1.613
Optical Character
Biaxial -
Physical Properties
Crystal Systemmonoclinic
Hardness (Mohs)5.0
Specific Gravity3.0
CleavagePerfect {110} at 56°
FractureSplintery
LustreVitreous to silky
Optical Properties
Refractive Index1.613
Birefringence0.022
Optical CharacterBiaxial -
Pleochroismmoderate: Yellow-green / Deep green
Colours
GreenDark greenGrey-green
Localities
TanzaniaMadagascarCanadaNew ZealandTaiwan
Common Inclusions
Fibrous structureMagnetite inclusions
Known Treatments
None commonly applied
Crystal Forms
prismpinacoid
Related Minerals
Other minerals in the monoclinic system
