Cold Chisel

A cold chisel is a hand tool made of tempered steel, used for cutting metal that has not been heated, in contrast to the hot work done at a forge. Like other chisels it has a wedge shaped cutting edge at the end of its blade and is driven by hand pressure or, more often, by striking its head with a hammer or mallet, but a cold chisel's cutting edge is ground to a less acute angle than a woodworking chisel's, trading some sharpness for the extra strength needed to cut metal without the edge chipping or rolling over. The tool is forged to shape, then hardened and tempered so the cutting edge itself takes on a blue temper color, distinguishing it visually from an untempered blank. Chisels of a similar wedge form go back to the Neolithic period, with stone examples found in Schleswig-Holstein, Germany dated to roughly 4100 to 2700 BCE, though the steel cold chisel used in metalworking today is a much later, purpose built development from that same basic idea.