Ferro-hornblende

minerals

wohlerite

hornblende

Formula: ☐Ca2(Fe2+4Al)(Si7Al)O22(OH)2
Inosilicate (chain silicate), amphibole group, forms a series with magnesio-hornblende
Specific gravity:
Hardness: 5 to 6
Streak: Pale grey-green, grey-white
Colour: Dark green to black, greenish-brown, more rarely lighter green
Solubility:
Common impurities: Ti,Mn,Na,K
Environments

Plutonic igneous environments
Metamorphic environments

Ferro-hornblende is found in granite and granodiorite, and is common in amphibolite and schist (Webmin, HOM). Associated minerals include hedenbergite (in granite), biotite, epidote, albite and quartz (in amphibolite) (HOM).

Back to Minerals