monoclinic Inosilicates
Actinolite (Prismatic)
Formula 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 System
- monoclinic
- Hardness (Mohs)
- 5.0
- Specific Gravity
- 3.0
- Cleavage
- Perfect {110} at 56°
- Fracture
- Splintery
- Lustre
- Vitreous to silky
Optical Properties
- Refractive Index
- 1.613
- Birefringence
- 0.022
- Optical Character
- Biaxial -
- Pleochroism
- moderate: Yellow-green / Deep green
Characteristics
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
