Item talk:Q162766
From geokb
Mindat Short Description
Mica Group.
No longer a species - a series of trioctahedral micas on, or close to, the siderophyllite-polylithionite join; dark micas containing lithium (Rieder et al., 1998).
-1M, -2M, and -3T polytypes are known.
The original zinnwaldite mat...