Wrought iron is the form in which iron was probably first known to man. The ancients reduced it directly from the oxide ores in small furnaces, using charcoal as fuel and depending at first for a blast upon the pressure of a strong wind to force air through a tuyere in the side of the furnace. The heat generated was barely sufficient to reduce the ore, and not high enough to cause an absorption of carbon to any degree, nor the decomposition of the silicon, phosphorous and manganese compounds. The iron, mixed with cinder and slag, was taken from the furnace in a pasty state (because it did not melt at the temperature of the furnace) and was hammered to squeeze these substances out.

This process was improved and enlarged, until finally the blast furnace was developed. As the degree of heat in the reducing furnace became higher, due to a closed furnace, thicker walls, more tuyeres and more rapid combustion of the fuel by improved methods of supplying a pressure blast, the production of pig iron gradually resulted in place of wrought iron.

Wrought iron was produced from the ore merely because the heat was not high enough to make the metal take up carbon, the absorption of which would have changed the product to pig iron.