Hornblende is a generic name for any dark minerals of the amphibole group.
You can see a hornblende stone for sale and buy it in the Minerals of Russia online store.
General | |
---|---|
Category | Silicate mineral |
Formula (repeating unit) |
Ca2(Mg,Fe,Al)5(Al,Si)8O22(OH)2 |
IMA symbol | Hbl |
Crystal system | Monoclinic |
Space group | C2/m |
Identification | |
Color | Black to dark green or brown |
Crystal habit | Hexagonal/granular |
Cleavage | Imperfect at 56° and 124° |
Fracture | Uneven |
Mohs scale hardness | 5–6 |
Luster | Vitreous to dull |
Streak | Pale gray, gray-white, white, colorless |
Specific gravity | 2.9 |
Pleochroism | Strong |