Sulfide Ore Treatment Gold – Silver – Copper – Cobalt – Zinc Recovery

A procedure was developed for recovering gold, silver, cobalt, copper, and zinc from a massive sulfide ore by a hydro-metallurgical process. The procedure consists of (1) oxygen pressure leaching; (2) iron, arsenic, and copper removal from the leach solution by precipitation; (3) selective extraction of cobalt and zinc from solution; (4) electro-deposition of the cobalt […]

Assaying

Assaying for ruthenium, rhodium, palladium, silver, osmium, iridium, platinum, gold is performed by fire assay. This ancient form of quantitative chemical analysis by which metals are separated and determined in ores and metallurgical products with the aid of heat and dry reagents. At present, this technique is used principally to preconcentrate the noble metals from […]

Free Milling Gold Laboratory Testing

Friends often ask how accurate the work of our little stamp-mill is, or express the opinion that a little mill cannot do good work. As a reply we would like to place on record the results of a few tests. There are two periods of work in our laboratory; the fall term, when the class […]

Extracting Tungsten from Wolframite Gold Ore

recover_fine_tungsten

The present great demand for tungsten due to world conditions has resulted in an increase of tungsten ore dressing problems for our metallurgists. The flowsheet study shown here was recently developed for treatment of a very complex tungsten-gold ore. The flowsheet study previously shown for tungsten was devised for a simple tungsten ore free of […]

How to Process Copper Lead Zinc Ore with Gold and Silver by Flotation

How to Process Copper Lead Zinc Ore with Gold and Silver by Flotation - 911Metallurgist

The flowsheet in this study was designed to treat 500 tons per day of a complex base metal ore containing gold and silver values. The presence of free gold offers opportunity to recover these values in the grinding circuit so that the gold could be amalgamated, and marketed directly to the mint. The ore as […]

Gold and Silver Leaching by Cyanidation

Gold Leaching Tank

Introduction to Gold and Silver Leaching The cyanide leaching process is the most important method ever developed for extracting gold from its ores. The early development of the process is attributed to a Scotchman, John Stewart Mac Arthur, in collaboration with the Forrest brothers. The method was introduced into South Africa in 1890. From there it spread […]

Illegal gold miner rescued after 13 days lost

800px Corcovado Strand Nationalpark

An illegal miner was found in the Osa Peninsula’s Corcovado National Park, in Costa Rica, where he got lost almost two weeks ago. Joel Cerdas Solórzano, locally known as “Pizote the gold miner”, went missing on January 23 while illegally mining gold inside the boundaries of the park. Three days later, a rescue team composed of officials from the National System […]

Mining process based on bacterias unlocks gold in South Africa

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A bacteria-rich process currently being used in Barberton, a town in the Mpumalanga province of South Africa, can help liberate ultra-fine gold locked in sulphide crystals. The experiment, called Biox technology, is happening in three mines owned by Pan African Resources. Besides these three pits, there are other five gold mines around the world currently using the biological oxidation […]

Yamana Gold’s Cerro Moro Mine by Numbers [infographic]

CerroMoroMine

Despite the fact that the mining industry is living dark times, especially due to the downfall of gold’s price, the company Yamana Gold is definitely developing its Cerro Moro gold and silver project. The deposit, located in the southern Argentine province of Santa Cruz, will move forward thanks to an initial investment of $450 million. […]

Top five countries that lost most gold in 2013

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Each country’s central bank is usually known to hold gold reserves that basically just sit in vaults for years. However, the amount of gold each nation possesses represents, in most cases, a big part of its fortune.  The United States, for instance, has more than 8,000 tonnes of gold. But 2013 was tough for some […]