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cyanide process
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Also called:
Macarthur-forrest Process
Related Topics:
Elsner reaction
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cyanide process

metallurgy
Also known as: MacArthur-Forrest process, cyanidation
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History

cyanide process, method of extracting silver and gold from their ores by dissolving them in a dilute solution of sodium cyanide or potassium cyanide. The process was invented in 1887 by the Scottish chemists John S. MacArthur, Robert W. Forrest, and William Forrest. The method includes three steps: contacting the finely ground ore with the cyanide solution, separating the solids from the clear solution, and recovering the precious metals from the solution by precipitation with zinc dust.