Inquarting for a large lot of scrap gold

[1993gt40]

First post and have been reading a lot, thank you all for a wonderful resource in this community.

Have been working through a large lot of sterling and am about to embark on my first scrap karat gold refining. I have about 800g of scrap Karat gold which is mostly a mix of 10-14k with some 18 and 24 k mixed in, mostly yellow gold but a fair quantity of white gold (maybe 10%).

I mostly trust the lot I have which is composed of several hundred small bits of scrap, however, I am worried about inquarting too low a % of gold and winding up with a mess during refining if some filled or plated material found it’s way into this pile of material to refine.

My plan is to take the entire lot and melt it together before inquarting it and test the output of that pour for gold content. Based on that I would then calculate the silver content to add before inquarting and pouring into shot.

My question is whether or not this is a sound strategy, or should I go through the tedious process of acid testing this small mountain of scrap bits? I am willing to do that if that is what it takes but I was hoping to save the considerable time it would take to do that. However, I wanted to ask here first before I melted everything into one solid block in case that would create more problems for me in the refining process.

Secondary question, I do not plan to refine for PGMs as it is beyond my skill and equipment level as a hobbyist refiner, am I out of my mind to lose what small content of PGMs or should I work a trade of my white gold content with someone for yellow gold and let them recover whatever may be recoverable from this lot?

 

[Martijn]

Welcome to the forum.
Having no experience with gold filled or white gold.. here are my thoughts:
Melting it all together is probably not the best choice.
White gold can/will contain palladium, nickel and zinc and some have a rhodium coating. Besides silver, which you will use to inquart anyway.
Maybe i'm wrong but treating similar items together is better than throwing all sorts in together.

Inquarting to below 25% gold will result in fine gold powder intead of a gold sponge that remains together.
The latter will be easier to reach by the acid in the hard to reach corners. And easier to wash.

You will end up with PGM's in solution after processing the white gold and that will stay in the stockpot unitil you get the gold out and sell the black PGM powder.

I would sort yellow and white and according karat stamps and test suspicious items for gold filled. Unmarked is usually plated.
You can use an inquarting calculator for the different karats and caculate all the silver needed for the whole batch. Yellow and white separate... i will get corrected if this is not needed.
Here is mine: Needs a user friendly update. and don't mind the nitric calculation too much. It's an indication.

View attachment Karat Gold calculator-1 (1).xlsx

Martijn.

 

[nickvc]

Having done many many batches like this I’d simply calculate the gold content at 12 karat add the silver needed and melt together ensuring it is well stirred when molten, pour your cornflakes and proceed to your nitric where because if the presence of silver any platinum will follow the silver and any palladium will dissolve in nitric anyway and go with your silver. If you are worried about the PGMs you can convert the silver to chloride and filter and then cement the PGMs out using copper or simply cement the lot and recover the PGMs later using a cell when you think it’s worth the effort.