Lepidolite (Silicate-Phyllosilicate)
K(Li,Al)2-3(AlSi3O10)(OH)2Hardness: 2.5 - 4.0
Specific Gravity: 2.9
Characteristics: Lithium mica; lilac to rose-red, less commonly, yellow, gray, or white; vitreous to pearly luster; perfect basal cleavage; translucent; produces red flame from presence of Li; insoluble in most acids.
Found in lithium-rich pegmatites.
(Primary text: Perkins, D. 2002. Mineralogy. Prentice Hall.)