Firesteel

A fire striker (or fire steel) is a piece of carbon steel from which sparks are struck by the sharp edge of flint, chert or similar rock.

A Fire Striker is a specific tool used in firemaking.

In early times, percussion firemaking 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" called Ötzi may have used iron pyrite to make fire.

From the Iron Age forward, until the invention of the friction match, the use of flint and steel was a common method of firelighting. Percussion fire-starting was prevalent in Europe during ancient times, the Middle Ages and the Viking Age.

When flint and steel were used, 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 firemaking was performed, using agate or quartz. It was also used as a ritual to bring good luck or ward off evil.

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.) do not. The steel must be hardened but softer than the flint-like material scraping off the spark. Old files, leaf and coil springs, and rusty gardening tools are common, re-purposed sources of strikers.

Besides flint, many other hard, non-porous rocks can be used, that can take a sharp edge, such as chert, quartz, agate, jasper or chalcedony.

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