ingot-pitch

Century Dictionary and Cyclopedia

1. n. The pitch at which ingots are cast; noting a variety of tough-pitch copper in which the poling for the removal of dissolved oxygen has not been carried on as long as it has in the wire-bar pitch variety. The longer the poling is continued the freer will the copper be from oxygen. See over-pole. For ingots or cakes the amount of oxygen may be greater than for copper which is to be cast into wire-bars, which are rolled into rods and then drawn into wire for electrical conductors. As impurities reduce the conductivity of copper for electricity very greatly, the oxygen in such cases must be low. Electrochem. Industry, March, 1904, p. 90.