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Thiosulphate Gold Leaching (6 replies)

Victor Bergman
12 months ago
Victor Bergman 12 months ago

Using Thiosulphate Gold Leaching is nothing new but here is the first ever gold bar that doesn’t involve use of cyanide extraction. http://blog.csiro.au/eureka-a-solid-gold-solution-to-make-archimedes-proud/ link work that was done in 1890's

Similar to UBCs patent from 2001 http://www.google.com/patents/US6632264

John Koenig
12 months ago
John Koenig 12 months ago

First of all, Barrick Gold Corp is a Canadian Company with a subsidiary operation in the US, Goldstrike. Congrats to my friend and colleague, and his team for their dogged commitment to find a process for their specific mineralogy and specific challenges that allowed thiosulphate to be the lixiviant of choice. A lot of effort, scientific challenge, and commitment deserve. Many more have contributed since then to advancing the technology and potential niches for use. Even more sweat and tears from the likes of former CISRO member Dr Matthew Jeffries and Dr Paul Breuer who also contributed to the Barrick efforts. Innovation and technology are a result of combined efforts and global sharing well done.

However, which are the comparative and specific costs [ US$/ton of gold ] for both technology: thiosulfate vs cyanide? 

Bill Fraser
12 months ago
Bill Fraser 12 months ago

I would think there was a lot of gold bars made before the cyanide process was developed. Alluvial. Mercury etc.The Thiosulphate and resin process has been worked on for a long time. A great effort to get it working on a modern large scale plant and to really understand the fundamental chemistry involved.

Helena Russell
12 months ago
Helena Russell 12 months ago

You are is right on Bill, in fact even now long after cyanidation was developed there are some gold mines out there getting >90% recovery by gravity alone - specifically with Knelson Concentrators. These are hard-rock mines, not alluvial, typically using very high "gravity effort" and of course the ore must lend itself to this process.

Bob Mathias
12 months ago
Bob Mathias 12 months ago

Commendable effort keep it up!! Thiosulfate is one of alternative reagents to cyanide; many plants still uses cyanide as the primary reagent for gold leaching even though its side effects to environment are well known.

While thiosulfate is a potential option, you do need to look at the mineralogy of the deposit. It widely known that cyanide does not always work and some other process must be used. This may include pretreatment to make the ore leachable.

So always look at the ore and its characteristics, do not just assume that one process or another will work.


Alan Carter
12 months ago
Alan Carter 12 months ago

I believe this work is commendable and the ceasing of cyanide usage is welcomed. the risks of cyanide usage have been controlled fairly well over the past years, but to eradicate will be very well received by all in gold processing plants.

Comparison of the economics of thiosulfate vs cyanide processes will clearly speak of the feasibility on a commercial scale.Anyway congrats to the people involved.

12 months ago
David 12 months ago

THIS here is goodbye NaCN http://www.911metallurgist.com/blog/cyanide-free-gold-leaching-alternative

I have visited the plant. It's for real.

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