Why will a piece of flint produce sparks?
Flint produces sparks because it is so hard. However, pieces of flint are only striking tools, and the sparks themselves come from a sparking material such as pyrite – a compound of iron and sulfur – steel, or a composite metal with iron content. In the Stone Age, a firelighter was often a lump of pyrite, a firestone to strike it on and some dried moss or the tinder fungus sometimes known as touchwood. In medieval pistols, the flint created the spark by striking iron, while in today’s disposable cigarette lighters a friction wheel creates tiny sparks from a composite metal which ignites the flow of gas. Expensive lighters use piezoelectric quartz crystals to produce sparks. Why are candle flames yellow? The colour of a flame is the result of several factors – the temperature of the flame, the chemical composition of the fuel that sustains it and the eye’s ability to perceive it. The predominant yellow colour comes from burning carbon molecules. After the heat has stripped the wax from
