Shellac flakes, wax-free, ruby colored.
Shellac is a spirit-varnish resin.
Shellac varnish gives a smooth finish and a high polish. The film is tough but not completely water-resistant.
It is used as a primer for wood because it prevents any resin escaping and affecting the paint film and because it is impervious to the solvents ordinarily used for fresh oil paint.
Shellac is a resinous secretion of the lac insect. After the crude lac is gathered from the tree, it is crushed and graded and the largest particles, called “seed-lac”, are selected for making the best grade of shellac varnishes.
The lac is heated, squeezed through a cotton bag, and worked into a plastic mass ready for stretching. It is stretched, either on rollers or by hand, into a thin sheet about four feet square. The sheet is slowly cooled and is broken into the flake-like pieces which appear on the market. Shellac comes almost entirely from India, although it is also produced in small quantities in Burma, Indo-China, and Siam. Its constitution has been investigated, but results vary because the origin of samples is often indefinite or unknown.