A "book" of violet Lepidolite showing its perfect cleavage in one
direction (micaceous). This specimen is from Brazil.
Fine grained Lepidolite next to a
Tourmaline crystal.
CHEMISTRY K(Li,Al)3(Si,Al)4O10(F,OH)2
CRYSTALLOGRAPHY Monoclinic
CRYSTAL GROWTH AND HABITS Lepidolite forms tabular to prismatic crystals that are pseudohexagonal. It also forms coarse to fine scaly aggregates and is massive.
COLOR AND OTHER OPTICAL PROPERTIES Lepidolite is commonly violet but can range in colors form purplish to pink, rose and yellowish.
HARDNESS 2.5 across cleavage faces and 4 along the prism sides
SPECIFIC GRAVITY 2.8 - 2.9
LUSTER Vitreous to pearly
STREAK White
BREAKABILITY Perfect micaceous cleavage producing thin elastic sheets
OCCURRENCE Found in granitic pegmatites
ASSOCIATED MINERALS Tourmaline, Beryl, Spodumene, Amblygonite, Muscovite, Quartz, Topaz