All ferrous metals contain iron. They vary in strength low - flexible wire), medium coat hanger) to high (screwdriver). The determining factor is the amount of carbon in the steel. The easiest way to discover the carbon content is to grind the steel and observe the nature of the sparks. By grinding a sample of ferrous metals, comparing it to the sparks produced bu known samples (of steel) and cross-checking the properties and uses (reference), an accurate identification may be made..
Spark pattern and colour indicate the amount of carbon in steel.