This
variety of mica is attractive on account of its pink or lilac color. It
usually occurs in scaly, granular masses, which often have sufficient
coherence to admit of carving them into various ornamental objects,
such as paper-weights, small vases, and boxes. They are somewhat
easily scratched, since the hardness of lepidolite is only 2.5-4.
Lepidolite is often known as lithia mica, on account of its content of
lithium, four per cent to five per cent. This affords a criterion for
the determination of the mineral, as a fragment heated before the
blowpipe gives the purple-red flame of lithia.
The
principal European deposit of lepidolite which has been used for
ornamental purposes, is that at Rozena, in Moravia, where a quantity of
the mineral of an especially pleasing rose-lilac color occurs. In the
United States, lepidolite occurs at Paris, Rumford, and several other
points in Oxford County, Maine, and in California, eight miles from San
Diego. The deposit at the latter place is an extensive one, and is
mined for lithia salts. This "lepidolite" is penetrated by crystals of
rubellite, giving an effect as shown in the colored plate. Although
some of the American lepidolite is nearly equal to the European in
quality of color, no use seems as yet to have been made of it for
ornamental purposes.