Is flint really effective in starting a fire?
During prehistoric times, flint was a tool widely used by our ancestors, so much so that they were masters in the art of shaping stones into everyday tools. Knife blades, projectile points, scrapers, ax, these are all applications reserved for flint.
For many, flint was also used to create sparks. But can you really make a fire with a flint?
The flint needs to be helped by another pebble to produce sparks.
Flint is also called “fire stone”. The reason is simple, it was used to light the fire from prehistoric times.
Its use has never stopped in human history, so the first lighters in the 16th century used these small stones to generate sparks. They were even used in the first firearms during the Napoleonic era. But to start a wood fire, flints alone are not enough.
In reality, the flint must be smashed against an iron-rich stone. This is the case with pyrite, for example, or steel.
Iron particles ejected into the air catch fire and generate very hot sparks. These sparks easily ignite tinder, a material that makes up the tinder, a fungus that grows on tree trunks.
Where do the sparks come from when you hit steel with flint?
It’s the iron responsible. Iron is a metal that ignites immediately on contact with air even at room temperature. It is said to be a pyrophoric material. In simpler language, we speak of auto-ignition.
However, iron is rarely pure in everyday objects. On contact with air, it oxidizes to form a layer of rust on the surface of objects. And this layer of rust is an excellent insulator so that the iron present in the heart of the object is protected from air. That’s why you don’t feel a burn when you hold an iron object in your hand.
But when using pyrite, a natural stone rich in iron (FeS2), or steel, an alloy of iron and carbon, the percussion of flint causes the removal of small particles of iron which in contact with air ignite. That’s why you see thousands of little red sparks.