Float copper

(Mining) fine particles of metallic copper or of gold suspended in water, and thus liable to be lost.

See also: Float

Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
Researchers at the Michigan College of Mines (now Michigan Technological University) developed her idea further to find the best combination of oils needed to float copper particles.