thumb|Assorted reproduction fire steels typical of the ancient and medieval periods
thumb|Late 18th-century fire steels from Brittany
A fire striker or fire steel is a tool used in fire making, consisting of a piece of steel that can be struck against a flint, chert, or other hard rock in order to generate sparks.
History
Before the invention of matches, percussion fire making was often used to start fires. Before the advent of steel, a variety of iron pyrite or marcasite was used with flint and other stones to produce a high-temperature spark that could be used to create fire. There are indications that the Iceman, also known as Ötzi, may have used iron pyrite to make fire. From the Iron Age forward, until the invention of the friction match in 1826 by John Walker, the use of flints and steels was widespread. The fire steel was often kept in a metal tinderbox, together with flint and tinder. In Tibet and Mongolia, they were instead carried in a leather pouch called a chuckmuck.
In Japan, percussion fire making was performed using agate or even quartz. It was also used as a ritual to bring good luck or ward off evil. Ninjas used an Uchitake (打竹).
Uses
thumb|Fire striker and flint used in [[Dalarna, Sweden, in 1916]]
The type and hardness of steel used is important. High-carbon steels (1060, W1, tool steels, etc.) generate sparks easily. Iron and alloys (like stainless steel, 5160, etc.) are more difficult and generate fewer sparks. The steel must be hardened but softer than the flint-like material striking off the spark. Old files, leaf and coil springs, and rusty gardening tools are often repurposed as strikers.
Besides flint, other hard, non-porous rocks that can take a sharp edge can be used, such as chert, quartz, agate, jasper or chalcedony.