Crystal system Monoclinic | Space group C2/m | |
Category InosilicateAmphibole supergroup Formula(repeating unit) ☐Ca2(Fe4Fe)(Si7Al)O22(OH)2 Crystal class Prismatic (2/m)(same H-M symbol) Unit cell a = 9.93, b = 18.22c = 5.32 [Å], β = 104.86° (approximated) | ||
Ferro-ferri-hornblende is an amphibole-supergroup mineral with the formula ☐Ca2(Fe2+4Fe3+)(Si7Al)O22(OH)2. It contains essential vacancy (☐). It was discovered in the Traversella mine, Canavese, Torino, Piedmont, Italy.
References
Ferro-ferri-hornblende Wikipedia(Text) CC BY-SA