The cyanidation of gold ore with oxidized copper can have a high or low gold extraction. If gold extraction is low ( eg 30 % ), as can happen with mineral content indicated with the oxidized copper processing by cyanidation is not economical. But if gold extraction can be as high as 80 % for example, and much of the copper is dissolved, should investigate possible alternative treatment to recover gold and copper. In this case, the SART process is usually evaluated as a complementary process, allowing separate the soluble copper as a copper sulfide precipitate, and the solution containing gold may be sent to a process with activated carbon or zinc powder. If soluble copper is not removed, the final product will have high levels gold copper, the process is also affected with activated carbon or Merrill Crowe.

Should check up the Eh-pH diagram for copper. Copper oxide very much stable at the pH range employed in cyanidation, so cyanidation should work properly. Not the same if copper was a sulfide, in which case copper sulfide would increase cyanide parasitic consumption.

Bill

Copper oxides normally leach pretty well in cyanide solutions - you can see how well here https://publications.csiro.au/rpr/download?pid=csiro:EP112080&dsid=DS2

You are definitely in the "it's going to be problematic" zone" - the paper I've provided the link for gives an excellent overview though, and if you run through a quick metal balance you could get an idea of how much of a problem you may have, and if you are heading down a cold cyanide wash route, if it is more SART oriented or if you need to look at more exotic alternatives.

I don't think the paper includes the latest option for gold-copper ores by the way - this is GlyLeach, being punted by the lads from Curtin University, and something I think has huge potential.