Ferrocerium

Ferrocerium is a synthetic pyrophoric alloy that produces hot sparks that can reach temperatures of 3,000 °C (5,430 °F) when rapidly oxidized by the process of striking. This property allows it to have many commercial applications, such as the ignition source for lighters (often misidentified as the "flint" component), strikers for gas welding and cutting torches, deoxidization in metallurgy, and ferrocerium rods (also called ferro rods, flint-and-steel, and flint-spark-lighters). Due to ferrocerium's ability to ignite in adverse conditions, rods of ferrocerium are commonly used as an emergency combustion device in survival kits.

Invented by 1903 by the Austrian chemist Carl Auer von Welsbach, ferrocerium takes its name from its two primary components: iron (from Latin: ferrum), and the rare earth element cerium. The pyrophoric effect is dependent on the brittleness of the alloy and its low autoignition temperature.

While ferrocerium-and-steels function in a similar way to natural flint-and-steel in fire starting, ferrocerium takes on the role that steel played in traditional methods: when small shavings of it are removed quickly enough the heat generated by friction is enough to ignite those shavings, converting the metal to the oxide, i.e., the sparks are tiny pieces of burning metal. The sparking is due to cerium's low ignition temperature of between 150 and 180 °C (302 and 356 °F). About 700 tons were produced in 2000.

Modern flint bears no chemical relationship to the mineral flint, the name for two types of rock historically used to generate sparks. In traditional flint-and-steel fire-starting systems (using natural flint), an iron-bearing rock was used, which has a passing resemblance of modern flint, as it is iron in the tiny shards of rock produced in the striking process that burn.

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