Recommended setup to process 350oz of scrap jewery per week

Hello,

I live in Central America in a country where there is no real gold refinery. Most people here send any gold scrap and nuggets to the US to get refined and import refined gold when needing.

Through a lot of networking I have found a large jewelry maker that buys/imports 150oz of gold per week and have also found enough scrap sellers that can provide me with enough scrap jewelry to refine to meet the 150oz a week. There are other opportunities to refine gold in this country as there are mines in the area too sending gold away to the US to be refined.

Most of the jewelry around here is of the lower karat values... 12k 10k or even lower.
Small nuggets may be fairly available for us too.

I have read a lot and I have only done some refining on a small home scale to get familiar with the processes to learn and hoping to scale up. But my current setup I have been playing with is tedious and would not scale so easily. But before I start investing a ton in real equipment, I was looking for more opinions so I do not make any wrong/bad decisions and waste a ton of money.
I am also connected with the largest University and chemistry professors here that are on the team here.

Now, to my question
What is the best or recommended method/process to refine about 350oz of scrap low karat jewelry per week?

I have considered the Shor Simplicity electrolysis refinery since I would not need the acids and it works better with jewelry but I would need 3-5 of them running non-stop. I have also seen people no happy with it... Plus I could probably make my own setup/device cheaper if I wanted to go that route and knew what I was doing. I understand Aqua Regina method works better with higher karat gold pieces and the inquarting method maybe better for lower karat quantities which is what we would have more of.
I wonder if I should try to fabricate some of my own equipment and or just splurge and get a real ready made setup.
I would prefer to keep expenses low initially and reinvest in the better automated equipment later... Then my questions would be which equipment is worth it.

I would like to keep start up expenses less than $10k but ideally closer to less than $5k to be producing our first refined gold at a decent quantity. We could spend more once the biz starts and we see it all working according to plan.

Any suggestions/opinions would be much appriciated.
I would even consider consultation proposals.

Thanks,
Xen

I know many refiners who to this day refine karat scrap in aqua regia with only a hood and 5 gallon plastic pails. Each pail will hold approximately 100 ounces of karat for dissolution. The key to using 5 gallon pails is to melt your gold together into bars with the intent being silver content under 8% ideally. Then the gold can be granulated and digested in aqua regia. To do this properly you will need a gas melter, a basic fire assay setup, a hood and for the sake of those cute green Costa Rican tree frogs, a scrubber.

Fire assay on karat materials is pretty straight forward and the methods are detailed on on this forum. It will allow you to batch jobs together and pay on assay. Larger refining lots but less labor. If the silver is too high in your material you mat have to inquart with silver but that process is also well documented here.

I can see you getting it done for under 10,000 but under 5,000 will be hard to do. This method will only require 1 days work to refine the material and time for the individual assays.

xenfasa said:

Most of the jewelry around here is of the lower karat values... 12k 10k or even lower.

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4metals said:

with the intent being silver content under 8% ideally

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I think it will be next to impossible for him to reach, he will have to own 150+ Oz of 24K just to raise gold content...
The catch is... electrolysis set-up will demand it as well...

I've seen low karat without high silver. If the karat was lowered with CuZn alloy inquarting may not be required. As is so important in running batch lots in this business, you have to know what you are starting with, for that reason a small fire assay capability will pay off.

Good Point 4metals

assay assay assay

I was gonna say the 5 gallon bucket idea too but 4metals beat me to it. It was suggested to me in the past by... well... 4metals

I must admit I'm in full agreement with 4metals and had a post ready but I preferred his suggestions especially the assaying to determine the silver content.The only thing I might add to his list is a decent vacuum pump and filter set up, not cheap but speeds things up and worth the investment.

And you plan to sell your refined material to whom?. What are their minimum fineness requirements?. A simple inquarting/fluxing rig for less than $1,000 maybe all that you need to start.

Do you plan to do the 350 Oz once a week or 50-75 Oz per day?. It all goes back to: Who do you sell your gold to and at what price and fineness required?.

The complete fire assay lab will cost more, and certainly you'll need to be crafty to get it all done for less than $5,000. But... you'll probably have to accept the buyer's assay...so if you buy well, refine fairly, and accept the buyer's assay you do not need a fire assay lab to start (but it is a good nice thing to have, so get one soon!).IMHO.

If you use the scratch stone test for determining approximate karat and your margin under spot for buying is ample enough, you can pass on the fire assay lab to begin with. Now if the margins are tighter and/or you distrust your out's assay for fine material, then you need an assay lab, but that'll probably be a minor problem in comparison. You can't be negotiating/fighting with your out every time you sell a bar to him, so you'll have to accept to get minimally screwed on average, accept his assay values for your fine, and accept it as a "cost of doing business". :shock:

Frankly most of the time you can do the "reverse fire assay technique" TM by HAuCl4: Keep a sample of your fine, and only in case your buyer's assay comes out completely out of line with what you expect, then do the fire assay on the sample you kept. 99 times out of 100 you end up accepting the buyer's assay that come consistently within 2/10,000 of yours anyway, if you are doing business with a honest out. 8)

wow, thanks for all the great comments. This community is an unbelievable resource of info.
I am studying all of your comments and doing more reading and research according to all your suggestions. I will report back with more details, clarification and answers to your follow up questions very shortly. Meanwhile, I just wanted to let you all know you have been a big help. so thanks.

I knew a guy in the '80's who refined for a collector and never did any assays, he just accepted the collectors numbers, and all of his work was from 1 guy. Weekly he returned his out-turn less expenses and when he got around to cleaning up the chlorides and papers he was over 100 ounces short. What most likely happened was the collector "forgot" to apply the correction factor to the assays which added up to gold that was never really there. The assayer the collector used always provided uncorrected assays.

This industry today, and apparently in the '80's as well, is full of people who will take advantage of you. Be sure, assay yourself. It costs more up front, true no debate there, but I can't see the down side. Another benefit is it helps you track your own accountability, if you're doing quantity that matters as well.

4metals said:

I knew a guy in the '80's who refined for a collector and never did any assays, he just accepted the collectors numbers, and all of his work was from 1 guy. Weekly he returned his out-turn less expenses and when he got around to cleaning up the chlorides and papers he was over 100 ounces short. What most likely happened was the collector "forgot" to apply the correction factor to the assays which added up to gold that was never really there. The assayer the collector used always provided uncorrected assays.

This industry today, and apparently in the '80's as well, is full of people who will take advantage of you. Be sure, assay yourself. It costs more up front, true no debate there, but I can't see the down side. Another benefit is it helps you track your own accountability, if you're doing quantity that matters as well.

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Did the collector make the processor cover the 100oz?

That is expensive and hurts.

Everything must be put into perspective too. If you are really doing $400,000-$500,000 of gold per week, spending $5k-$10k in a modest assay lab is peanuts in the long run, and will quickly pay for itself like 4metals says (in peace of mind at least). Now if you are buying at 5% discount under spot, you have plenty margin for "errors", "thefts", and etc. I did repeat business for a long time with a "wise guy" that routinely pressed for his assays 5-7 parts per 1000 too rich to be accepted...I accepted and praised his "fine assaying skills", but kept paying him 3% under spot...Result: He was happy "screwing" me, and I was happy with my 2.3-2.5% on his volume that he would have taken to a competitor...yawn.

edit to add: You must watch your buy side, and have enough margin. Most screw ups come from that side, not from the sell side.

It put him out of the business. So he didn't make good on the gold but it changed his profession. He just shotted the bars and never sampled so if it had gone to court he would have had to pay.

Umpire rules and splitting limits have been around for a long time. And for good reason.

It is also a good idea to work on a per batch basis: After every batch all the accounting must be done. Inquarting and parting is great for this because it is fairly quick to isolate all values, and there isn't much gold trapped anywhere.

4metals said:

It put him out of the business. So he didn't make good on the gold but it changed his profession. He just shotted the bars and never sampled so if it had gone to court he would have had to pay.

Umpire rules and splitting limits have been around for a long time. And for good reason.

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That was a hard lesson to learn and I hope it hit's home here on the forum. Keep up with what you have coming in and what goes out and make sure you adjust for the difference.

That is a valid option as well but if the 350 ounces comes in as 25 lots the labor is considerable. A well done setup will enable him to process larger lots efficiently, running 25 individual lots from receiving to fine gold melt is labor intensive. But cheaper to start.

If that is the approach chosen, individual lots, then inquarting with silver based on incoming weight is the easy approach. He will quickly need to learn the art of the silver cell as he will be getting close to a kilo of silver a week out of the karat.

I hope there is consideration given to properly dealing with the waste acids. Just thinking about those Costa Rican tree frogs again.

Right. Or start with scrap copper or zinc or brass as the added metal for inquartation till he accumulates enough silver from the karat scrap. Silver is currently too expensive (IMO) to be buying it just for inquartation purposes. :idea:

He can evaporate the copper/zinc nitrate solution in the sun in a closed container, and when all the water is gone distill/recover the nitric acid from the crystals with some wood borrowed from the frogs. :lol:

Yes running in 25 small lot's is a heck of a lot more labor intensive and a lot more possability of losses if he has a lack of experience. His best bet would be to keep up with is returns and find out where he has discrpenecies in his figures and adjust his processing figures on this. Processing the amount he is talking about can put him out of buisness real quick if he dosen't analyze what his returns are. He needs to slow down and learn what he is doing in small lots till he has his process down pat.

HAuCl4 said:

Right. Or start with scrap copper or zinc or brass as the added metal for inquartation till he accumulates enough silver from the karat scrap. Silver is currently too expensive (IMO) to be buying it just for inquartation purposes. :idea:

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:roll: I think its time to change your lightbulb

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