- a mineral of the mica group, potassium lithium aluminum silicate, commonly occurring in lilac, rose-colored, or whitish scaly masses: an ore of lithium.
- a lilac, pink, or greyish mica consisting of a hydrous silicate of lithium, potassium, aluminium, and fluorine, containing rubidium as an impurity: a source of lithium and rubidium. Formula: K 2 Li 3 Al 4 Si 7 O 21 (OH,F) 3
