The process of making gas mantles originally involved several steps, beginning with the knitting of the cotton/silk fabric. The saturation step the fabric was saturated in lighting fluid. This fluid contains the thorium and cerium salts. The fabric was then dried on wood or glass forms and then carefully plaited together. An asbestos cord was drawn through to form a loop. The fabric was then shaped to fit a mantle by fitting it over a wooden form. It was estimated that American consumers used 40,000,000 mantles per year when gas lighting was commonly used.

The mantle is fixed over an orifice carrying a flammable gas such as natural gas, coal gas, propane, or vaporized benzene or other fuel. When the gas is ignited, the mantle fabric burns away, leaving a brittle residual lattice of metal oxides. Light is produced when this lattice is heated to glowing by the gas combustion, although the mantle itself does not burn.
Gas lamps may operate without mantles.

Cerium nitrate has been used in the manufacture of incandescent gas mantles. The metal serves as an ingredient in the carbon-impregnated arc lamps that have been used for illumination in the motion-picture, television, and related industries. Cerium is iron gray in color and about as soft and ductile as tin. It oxidizes slowly in air, rapidly reacts with water to yield hydrogen, and burns brilliantly when heated.

Dr. Carl Auer von Welsbach was an Austrian chemist and engineer who invented the incandescent gas mantel or "Auerlicht", thus allowing the greatly increased output of light by gas lamps. In 1885 Welsbach discovered and isolated the elements neodymium and praseodymium from a mixture called didymium, which was previously considered an element. His interest in rare-earth elements continued, and he found that a fabric impregnated with a mixture of thorium nitrate and cerium nitrate could be made into a mantle that glowed brightly when heated by a gas flame. Patented in 1885, the Welsbach mantle greatly improved gas lighting and, although largely supplanted by the incandescent lamp, is still widely used in kerosene and other lanterns. In 1898 Welsbach introduced the first metallic filament for incandescent lamps. Although the osmium he used was too rare for general use, his improvement paved the way for the tungsten filament and the modern light bulb. Welsbach also developed misch metal, a mixture of cerium and other rare earths, which he combined with iron to make Auer's metal, the first improvement over flint and steel for making sparks since ancient times. It is used in cigarette lighters and in strikers for lighting gas jets.