Its basis is resin lac, a compound resinous substance exuded from an East India scale insect (_Carteria lacca_) found mostly in the province of Assam.

The term "lac" is the same as "lakh" which means 100,000 and is indicative of the countless hosts of insects which are the source from which this gum is obtained.

The larval insects insert their proboscides into the bark of young shoots of certain lac-bearing trees, varieties of Ficus, draw out the sap for nutriment, and at once exude a resinous secretion which entirely covers their bodies and the twigs, often to the thickness of one-half inch.

The females never escape and after impregnation their ovaries become filled with a red fluid which forms a valuable dye known as lac dye.

The encrusted twigs are gathered by the natives in the spring and again in the autumn, before the young are hatched, and in this condition the product is known as "stick lac." After being crushed and separated from the twigs and washed free from the coloring matter the product is known as "seed lac." It is then melted and strained and spread out in thin layers in a form called "shell lac." This is what is known as orange shellac in the market.