Zinnwaldite

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 material came from Cínovec / Zinnwald (Cinvald), Erzgebirge; Krusné Hory Mts, Saxony & Ústí Region (Bohemia; Böhmen; Boehmen), Germany & Czech Republic.