Separating antimony from gold

Blakey · Sep 11, 2017

Hi all,
So over the weekend I tried to process my gold bearing ore with aqua regia and failed yet again. The ore is milled quartz breccia with free gold and stibnite, all other minerals/elements are negligible. The stibnite content is pretty high and it is dissolving in aqua regia and precipitating when I add the sodiuim metabisulfite.
How would I separate the antimony from the aqua regia before the gold?
Cheers

kjavanb123 · Sep 11, 2017

Stibnite that I encountered during my mining era smelled like sufur, so it is sulfide of antimony, therefore it needs to be roasted in air to remove the sulfur.

This is just my 2 cents.

Regards
Kj

rickbb · Sep 11, 2017

If it's free gold wouldn't you just crush it fine and water separate it instead of using AR? Or does the stibnite contain gold as well?

Iggy-poo · Sep 11, 2017

You might want to look at this paper:

http://saimm.org.za/Conferences/PbZn2008/121-132_Anderson.pdf

Blakey · Sep 11, 2017

Thanks for the replies all.
Unfortunately I don't think I can roast the ore in my backyard. There is some arsenopyrite in the ore and the toxicity of the fumes that would be generated would not be good.
The ore contains mostly free gold but some is refractory gold in pyrite, arsenopyrite and aurostibite. I am only looking to recover the free gold at this stage. I have tried water separation but it is slow and cumbersome to pan or run over my miller table and I am losing an unacceptable amount due to the fineness of the crushed ore (<75micron).
The article you linked Iggy-poo is a good read! Page 129-130 seems to be what I'm looking for but I'm unsure how exactly to do this process in a backyard setup. I'll look in these forums and see if there is some info on alkaline gold recovery similar to this article.
Anyone know if those gold cube devices would recover milled free gold or would it be too fine and flow out?