Lac

Lac, a resinous incrustation formed on the twigs of various East Indian trees by the puncture of an insect, Coccus lacca. The name, meaning a hundred thousand, suggests the number of these insects, which pierce the bark with their proboscides and cover themselves with the resinous exudation. A red fluid collecting in the enlarged ovary of the female insect forms the lac-dye of commerce. Lac encrusting the twigs is known as stick-lac, and contains about 68 per cent. resin and 10 per cent. lac-dye. Stick-lac crushed and washed becomes seed-lac, and this when slowly melted in a cloth bag and spread out in thin layers on glossy plantain leaves constitutes shell-lac or shellac. Lac comes chiefly from Bengal, Assam, Pegu, and Siam, 6,650 tons of shellac being exported in 1890, mostly to England. Lac is a principal ingredient in sealing-wax (q.v.), and in many varnishes.