Example – Magnesiocarpholite, MgAl2Si2O6(OH)4
The carpholite group includes ferrocarpholite, magnesiocarpholite, vanadiocarpholite, and potassiccarpholite. The name derives from Greek karfos for “straw” and lithos for “stone” due to its crystal habit.
The crystal structure of a Mg-rich carpholite
Locality: southeast Sfinari, West Crete
American Mineralogist 66 (1981) 1080-1085
AlO6 octahedra (blue)
MgO6 octahedra (green)
SiO4 tetrahedra (orange)