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blister copper

noun Metallurgy.
  1. a matte of from 96 to 99 percent copper, having a blistered surface after smelting because of gases generated during solidification.

Origin of blister copper

First recorded in 1860–65
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for blister copper

blister copper

noun
  1. an impure form of copper having a blister-like surface due to the release of gas during cooling
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012