Leaching

Cementation of Gold by Zinc: Dilute & Foul Cyanide Solutions

Some months since, the attention of the author was directed to certain statements to the effect that the gold-contents of foul or extremely dilute cyanide-solutions could not be effectively precipitated in practice by the usual zinc cementation of gold called the “zinc-method”. Such statements caused all the greater surprise, because it is well known that … Read more

Leaching Sulfides by Sulphuric Acid: Copper

The improvement in leaching introduced by the Russell process has stimulated the development of processes for refining lixiviation-sulphides. In the early days several processes for dealing with the sulphides were proposed, and some of them were tried more or less ; but the business finally settled down to sending the sulphides to the smelters, although … Read more

Cyanide Chemistry & Gold Extraction

The fact that many millions of gold have been extracted by the cyanide process, during the last five or six years, from South African tailings which could not be profitably worked by any other method previously tried upon them, lends a peculiar practical interest to this branch of metallurgy. Numerous writers have recently made valuable … Read more

Silver Chlorination Leaching by Trough Method

In tank-lixiviation of silver by chlorination, the extraction of the silver from chloridized ore by solutions of hyposulphite salts is performed by filtration. The ore-particles are kept stationary, while the solvent moves down through the mass of ore. The quickness of extraction, other conditions alike, is in direct proportion to the rapidity of the movement … Read more