Ferrocerium is a synthetic pyrophoric alloy of mischmetal hardened by blending in oxides of iron and/or magnesium. When struck with a harder material, friction produces hot fragments that oxidize rapidly when exposed to the oxygen in the air, producing sparks that can reach temperatures of 3,315 °C (6,000 °F). The effect is due to the remarkably low ignition temperature of cerium, between 150 and 180 °C.

Cerium is a chemical element; it has symbol Ce and atomic number 58. Cerium is a soft, ductile, and silvery-white metal that tarnishes when exposed to air. Cerium is the second element in the lanthanide series, and while it often shows the oxidation state of +3 characteristic of the series, it also has a stable +4 state that does not oxidize water. It is also considered one of the rare-earth elements. Cerium has no known biological role in humans but is not particularly toxic, except with intense or continued exposure.