Aqua Regia order of precip question

[sfuller5]

after digesting black sand concentrate in heated Aqua Regia boiling down 3x of HCL we have the syrup photographed. Stannous check shows positive for Au, and Pt, we're pretty sure there is a good amount of Rh in the solution as well. What is the precip order recommended?

 

[Geo]

Gold first and PGM's second. Any silver should precipitate out when the solution cools or you dilute it with water.

 

[sfuller5]

Thanks Geo,

I was planning on using SMB for the 'Au precip, followed by Ammonium Chloride for the PT

 

[jeneje]

Once the Au has dropped, you will need to concentrate the solution down to get the Pt.

Ken

 

[jeneje]

Just curious here, did you have any assay's done on the material? Also, it would stand to reason if you have Pt, you would also have tested positive for Pd because they tend run together.

Ken

 

[sfuller5]

I forgot to mention Pd positive as well. As far as assay results I have not had an assay done on the black sand cons. A neighboring miner just up river had a spectrum analysis done that indicated all 5pgms were present in his concentrates. There was at least 5 grams of micro fine gold visible in the batch digested, this is left over after removing around 15oz of au using a gold wheel. We moved into a new previously un-mined area in a canyon that has several contact zones with mineralized veins (lot of copper) eroding into the section we're mining. The photo is a handful of the concentrates prior to running through gold wheel.

 

[jeneje]

Nice, very nice pan. Just to let you know there are better ways to recover the precious metals other than using AR. I am not up-to-date on them but, maybe Harold_V, Lou or one of the other Moderators will chime in to help out.

I would think once the cons have been concentrated down as-far-as one could go with mech. equipment, smelting with a flux would be the next step. Anyways, the Gold looks beautiful in the pan.

Ken

 

[4metals]

Just to let you know there are better ways to recover the precious metals other than using AR. I am not up-to-date on them but, maybe Harold_V, Lou or one of the other Moderators will chime in to help out.

This thread should be quite valuable.http://goldrefiningforum.com/phpBB3/viewtopic.php?f=37&t=21526

 

[sfuller5]

Thanks much for the help & the thread post, I'd love to spend lab time with Deano! grateful for the wealth of knowledge he's passed on here!