An intermediate product in the smelting of copper, containing about 75 per cent or more of copper and having pimples on the surface formed by escaping bubbles of sulphur dioxide.
Origin
Late 19th century; earliest use found in Charles Bloxam (1831–1887), chemist.
Definition of pimple metal in US English:
pimple metal
noun
Metallurgy
An intermediate product in the smelting of copper, containing about 75 per cent or more of copper and having pimples on the surface formed by escaping bubbles of sulphur dioxide.
Origin
Late 19th century; earliest use found in Charles Bloxam (1831–1887), chemist.