Gold 18carat

[arthur kierski]

i have 18carat gold jewels-collars ,wedding rings,bracelets etc-this cames from pawn banks (shops) that the client did not pay the loan back.I need to recuperate the gold --i did a lot of gold refining,but not from 18carat gold.How would one begin the process? thanks to all ,yours Arthur Kierski

 

[Yggdrasil]

i have 18carat gold jewels-collars ,wedding rings,bracelets etc-this cames from pawn banks (shops) that the client did not pay the loan back.I need to recuperate the gold --i did a lot of gold refining,but not from 18carat gold.How would one begin the process? thanks to all ,yours Arthur Kierski

Please drop the all bold text.
If you know it is 18 karat, depending on the alloy it can go directly into AR.

 

[goldandsilver123]

Dissolve with aqua regia,
Filter
Precipitate with sodium metabissulfite

There will leftovers that can be reworked

Or

Inquart
Dissolve with HNO3
Filter
Dissolve with aqua regia
Filter
Precipitate with sodium metabossulfite

 

[arthur kierski]

Please drop the all bold text.
If you know it is 18 karat, depending on the alloy it can go directly into AR.

Sorry,i will not extend my text anymore.I just wanted to tell the source of the materials.

 

[4metals]

Inquart
Dissolve with HNO3
Filter
Dissolve with aqua regia
Filter
Precipitate with sodium metabisulfite

This would be my. choice. All of my refining was done in a commercial environment where time was everything. As a result I typically used straight aqua regia unless the Silver assay was in excess of 9%. But this always resulted in clean gold (+99%) which required a second refine to maximize purity and insoluble crumbs of Silver Chloride encrusted Gold which required a separate refining. And it resulted in Silver Chloride in need of processing.

The inquart method is more nitric intensive but the nitric digest and parting can be done in stainless steel so larger lots are easier to process. Plus the parting will result in at least the (+99%) pure Gold which can be cleaned up with a single aqua regia dissolve. But the Silver is now all in one place and easily cemented with copper to a metal which can be used for future inquarts and as it accumulates refined to fine Silver.

 

[seasoned-TH]

i have 18carat gold jewels-collars ,wedding rings,bracelets etc-this cames from pawn banks (shops) that the client did not pay the loan back.I need to recuperate the gold --i did a lot of gold refining,but not from 18carat gold.How would one begin the process? thanks to all ,yours Arthur Kierski

Use the aqua regia method.
You have a few choices for percipitators

 

[4metals]

Use the aqua regia method.
You have a few choices for percipitators

Please explain your logic for this statement.

 

[nickvc]

One big advantage of inquarting with silver is that any PGMs which are quite likely if your son is processing mixed jewellery scraps will follow the silver into solution , once cemented and melted they can be recovered from the slimes by removing any silver with hot sulphuric baths leaving concentrated PGMs which makes separation much easier.

 

[arthur kierski]

One big advantage of inquarting with silver is that any PGMs which are quite likely if your son is processing mixed jewellery scraps will follow the silver into solution , once cemented and melted they can be recovered from the slimes by removing any silver with hot sulphuric baths leaving concentrated PGMs which makes separation much easier.

Thanks once again--he did not inquart yet---as soon as he does,ilet you know.

 

[4metals]

I have a client who we set up to do exactly what Nick says on a large scale.

He brings in a lot of silver scrap which he uses to inquart all of his karat scrap from the jewelry industry. Ironically he never refines gold to purity above about 999 and uses this technique to catch all of the PM's that are in low enough concentration that his refiner never pays on them.

He happily produces pure Silver and his slimes teach him exactly how those small quantities of PM's that the majors don't pay on add up.

His gold is shipped to a refiner who pays him at an excellent rate because the gold goes directly into the electrolytic feed saving the refiner a step.