Lepidolite (KLi2Al(Al,Si)3O10(F,OH)2) is a lilac or rose-violet colored phyllosilicate mineral of the mica group that is a secondary source of lithium. It is associated with other lithium-bearing minerals like spodumene in pegmatite bodies. It is one of the major sources of the rare alkali metals, rubidium and caesium.
Color: violet lombo pale pink to white, sometimes gray or yellow.
Luster: vitreous to pearly
Transparency: transparent to translucent.
Crystal System: monoclinic; 2/m.
Crystal Habits: include tabular to prismatic crystals with a prominent pinacoid termination. Lepidolite forms pseudo-hexagonal "books." Also as micaceous or granular masses.
Cleavage: perfect in one direction perpendicular to the c-axis.
Specific Gravity: 2.8+
Density:2.8-2.9 Average size 2.84
Associated Minerals: quartz, feldspar, spodumene, amblygonite, tourmaline.
Notable Occurrences: Brazil; Ural Mountains, Russia; California; Tanco Pegmatite, Bernic Lake Manitoba, Canada.