cyanide process

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A process of extracting gold or silver from ores by treating them with a solution of sodium cyanide or calcium cyanide.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A method of extracting gold and silver from their ores with a solution of sodium cyanide
• noun A process of case-hardening iron or steel by immersing it in molten cyanide and then quenching in water or oil

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun an industrial process for extracting gold and silver by treating ore with a sodium cyanide solution