# Gold filled material and stainless steel



## Orofromtheboro (Oct 10, 2019)

Hey everyone I am new to this forum and gold refining. I have been doing a lot of reading on the subject and watching videos. I've gone as far as getting some gold filled material ( mostly watches and the bands with the gf tops) I am not ready to begin to try refining yet as I need much more knowledge on the subject. I broke down the watch bands, catches etc and most of the material is magnetic. I am worried about any stainless steel ending up in my material when I eventially go to add nitric and break down the base metals. How do I get rid of any stainless steel? Also if it does end up in the solution will it break down in the nitric and how would I go about removing it without creating a mess or losing gold? Thank you for any help much appreciated.


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## FrugalRefiner (Oct 10, 2019)

Welcome to the forum Oro. I hope you didn't pay too much for your material. Any time you're dealing with gold plated or gold filled items, all the gold is on the surface, which is subject to physical abrasion, which can quickly wear away much of the gold. Necklaces and earrings aren't subject to much wear. Watches and watches are. It's just part of learning this craft.

In general, we try to either eliminate base metals before we dissolve our precious metals, or selectively dissolve the gold while leaving the base metals intact. Either way, the process isn't perfect, so we always end up with a solution that contains both values and base metals. We use reducing agents that are selective for our values, so in theory, we only reduce the values and leave the base metals in solution. If we want greater purity, we simply dissolve the relatively pure values a second time, reduce them a second time (perhaps with a different reducing agent), and we end up with very pure gold.

Dave


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## Orofromtheboro (Oct 10, 2019)

Hey Dave thanks for the reply. Haha I probably did pay too much but I'm not too upset about it. Like you said it's a learning process and I'm at the beginning. I hoping for this to be more of a hobby as it it very interesting to me. Getting gold from it is just a bonus as far as I'm concerned. But what I believe yoire saying is that you just remove the gold and leave the base metals? How do you achieve this with an AR? I'm very new and I've mostly been reading and watching how to using nitric acid to remove base metals and then AR at the end. There is so much I need to learn haha.


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## Williamjf77 (Oct 11, 2019)

Along the same lines, I am finishing up my first larger for me batch of gold filled and I had some eyeglass frames that the base metal didn’t dissolve in nitric and didn’t dissolve in AR. Actually I was able to pull the gold plate off in tubes around the wire.

Silver metal which I think is stainless steel? But not sure. It is magnetic.

Just did the drop so I’m waiting for it to settle.


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## FrugalRefiner (Oct 11, 2019)

Orofromtheboro said:


> But what I believe yoire saying is that you just remove the gold and leave the base metals? How do you achieve this with an AR?


In general, you don't. I was referring to using other methods to remove the gold selectively, like using a sulfuric acid stripping cell or cyanide.

Dave


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## nickvc (Oct 12, 2019)

When you have stainless you can use reverse AR where you use nitric in quantity and add very small amounts of Hcl to dissolve the karat away as stainless passivates in nitric alone, you will probably dissolve some stainless but it should be minimal.


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## snoman701 (Oct 12, 2019)

I’ve used RAR for gf watch bands...more of a pain than anything. Now I just dissolve base metals and then hit it hard and fast with excess oxidizer. You lose minimal gold to cementation.

Not to say it doesn’t work, just that without the means to use solvent extraction or ion extraction, killing a liter of nitric for five or ten grams of gold is a frustrating endeavor. 

At that point I’d rather use a strong cyanide leach like Harold used to do. 


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## kurtak (Oct 12, 2019)

snoman701 said:


> I’ve used RAR for gf watch bands...more of a pain than anything. Now I just dissolve base metals and then hit it hard and fast with excess oxidizer. You lose minimal gold to cementation.
> 
> Not to say it doesn’t work, just that without the means to use solvent extraction or ion extraction, killing a liter of nitric for five or ten grams of gold is a frustrating endeavor.
> 
> ...



snoman

Per the underlined - not really - you don't need to "kill" the huge amount of nitric after using the RAR for gold plated &/or gold filled on SS items

In other words - instead of "killing" the nitric - "use" the nitric 

If I have some gold plating on SS - I first use the RAR on the gold plated SS which dissolves the gold plating & leaves the SS

Then - because the RAR has a huge amount of free nitric in it - instead of trying to kill all that free nitric to drop the gold with say SMB - I "use" up all that free nitric to "recover" gold plating from other gold plated items where the gold is plated to brass or copper

so the result is the recovery of the gold foils plated on the copper items while at the same time the gold in the RAR is cemented out of the RAR by the copper being dissolved

When it comes to plated or GF its all about recovery first & then refining anyway so if you have gold on both SS & copper/brass you can use that to your advantage if you use the RAR "first" on the SS items & then on the copper items --- the "recovered" gold all ends up in the bottom of the beaker (or bucket) :mrgreen:

I have done some "large" batches of both gold plat & GF just this way & it works well 

What I don't get is why people don't use copper for gold "recovery" more --- I use it ALL the time when the recovered gold is going to have to go back to a "refining" process anyway

Kurt


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## snoman701 (Oct 12, 2019)

Trust me....I went thru all the options. 

I don’t especially like mixing my batches...mostly because without icp to know what’s there, I can’t track what I’m making.

But with watch bands I just don’t see the point in worrying about it. If you hit the fouls hard and fast with excess oxidizer, you don’t lose much gold to cementation on the stainless...the stainless is pretty slow to react. 

Now....you start talking about a process where you are stripping gold from stainless, and passivation becomes necessary. And in my experience, so does the use of another extraction mechanism...because it’s less likely that you only have a liter of it. 

I also worry about precipitation of gold with copper. Stannous becomes harder to read with that much copper in solution, and less reliable with excess oxidizer present. 



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## kurtak (Oct 13, 2019)

snoman701 said:


> I don’t especially like mixing my batches...mostly because without icp to know what’s there, I can’t track what I’m making.



snoman

first I want to say that when it comes to refining nothing could be more true then the old saying - "there's more then one way to skin a cat" --- in other words it comes down to personal preferred methods based on things like chems available, experience, types of material, etc.

Generally speaking we tell (new) members not to mix batches of material - as in don't go throwing a bunch of "different" material in a bucket full of acid & that is because a lot of different metal can be involved in the different material & different acids react differently with the different metals so you can end up making a "real mess" --- then also we tell (new) member to separate material by material "type" so they can get a handle on the process of that material type & as well get an idea of yield from that material type

After that - in my opinion (if I am working with my own material) why would I not mix material if those mixed materials are all compatible with the same process

Example; - I have a batch of fingers (gold plate on copper) a batch of pins (gold plate on brass) & a batch of gold filled on copper & I intend to recover the foils from each of those batches using nitric to dissolve away the copper/brass

Why in the world would I run 3 different batches - wash the acid out of the foils (3 times) AR the foils (3 times) drop the gold (3 times) wash the gold (3 times) & melt the gold (3 times) --- when - because all that material is compatible to the same process I can run it all as one batch

In other words - after years of doing this I already have a reasonable expectation of "foil recovery" from each type so I can already calculate a reasonable total expected yield whether I run it as 3 batches - or as one batch

Now per the underlined in the above quote; - the only reason I would need an ICP (or AA) is if I am mixing a costumers material with mine so that I can account to the customer

Another words I would then need to keep the foil recovery separate - then AR the costumers foils - ICP it to give the customer an accounting --- then do mine - then mix the two so I only have to do 1 drop, 1 wash, 1 dry & 1 melt --- if I had an ICP - I don't so I do a costumers separate from mine

Now concerning using acids - why would I use fresh acid in a second process if I have usable acid left from a previous process - that makes no sense to me

Example; - I just got done with a batch of foil recovery from some fingers - then I also did an AR leach on some chip ash

Because I used an "excess" of nitric in my AR leach to "insure" all the gold was leached from the ash 

Therefore - because I "know" the AR leach still had plenty of free nitric in it I then poured the filtered AR leach in a beaker with the foils to dissolve the foils 

The point being - its all my gold - if I put all the gold in solution I am going to get all the gold back when I go to drop it - the question being --- why in the world would I use "fresh" acid to dissolve the foils when the AR leach still as plenty of acid in it to dissolve more gold --- seems like a waste of acid to me



> I also worry about precipitation of gold with copper. Stannous becomes harder to read with that much copper in solution,



Why are you "worried" about precipitating gold with copper - using copper to "recover" gold from very dirty solutions has been a standard practice in large refineries forever - it was one of the first things I learned from people like Harold, 4metals, nickvc, & GSP when I first stated learning all of this something like 11 - 12 years ago & copper has been my "recovery" go to tool ever since


Copper (if its the primary metal in solution) is not going to mask your stannous test in fact it is far less likely to mask you stannous test then other metals (say like the metals in solution from doing a batch of ceramic CPUs)



> and less reliable with excess oxidizer present.



Thats just not true - in fact that is one of the points to using copper "when there is an excess of oxidizer"

The copper uses up ALL of the oxidizer - which in turn then allows the copper to cement out ALL of the gold

if there is an excess of oxidizer - when you first put the copper in - it starts out as a redox reaction (reduction & oxidation taking part at the same time) 

in other words - at first it starts to cement out the gold (reduction) but then because there is still free oxidizer it also re-dissolves the gold (oxidation) so both are happening at the same time --- but then - once the oxidizer is used up by the copper it then starts cementing the gold out as a "reduction" only process

That reaction will then take place until there is no acid left to dissolve copper - so when that reaction stops ALL of the gold has precipitated - pull the copper out - rinse it off & let your gold settle (along with stannous testing of course)

The only question is (remember we are talking a recovery process not a refining process) is how much copper contamination you end up with

In all my years of doing this (& well over 1,000 times) the very worst I have ever had my gold come back was 97 plus & I have had "a lot" of it come back as high a 99 - 995

When I was over in England & met with Jon, Goran, Nick, Pat & Deano - I did a batch of ceramic chips (pic) which gave me a VERY dirty solution with lots of free nitric (to insure all metals were dissolved)

I cemented that solution with copper - we hit the expected yield "on the nose" & XRF read out on the gold was 995 

Kurt


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## snoman701 (Oct 13, 2019)

Using fresh acid has never failed me. Trying to use every last bit of nitric to save 50 cents in acid has. 

As I build more confidence that may well change...but the less variables I introduce, the less likely I am to get bit in the butt.

If I have a solution with excess nitrates, it is kept segregated from start to waste treatment. I have a separate barrel for waste with nitrates.


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## snoman701 (Oct 13, 2019)

My point was that after rar, there are a lot better ways to get your gold back that don’t involve turning nitric acid into NOx.

For one, just add an excess of silver nitrate. Your gold will drop, albeit contaminated with agcl. 

I’ve made enough NOx chasing low grade material for a lifetime. Greener pastures ahead....or at least more profitable and environmentally sound processes. 


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## kurtak (Oct 14, 2019)

snoman701 said:


> Using fresh acid has never failed me. Trying to use every last bit of nitric to save 50 cents in acid has.



Snoman

you missed my point

in my example of of using my chip ash AR leach which had excess nitric to then dissolve my foils with that AR leach

it's not about doing that just to use up the free nitric & there by use up 50 cent of acid (although it does that to)

rather - its about using that acid to make one larger batch of AuCl so I can drop one large batch of gold instead of making two smaller batches of AuCl - having to drop 2 batches of gold - wash 2 batches of gold - dry 2 batches of gold - melt 2 batches of gold

the end result is I save time doing one batch instead of two - create less waste & yes - although the acid cost is not a big factor I also use less acid

using gold to use up the free nitric in an AR solution is an old trick Harold taught me in the first few months when I first joined the forum

Harold would dissolve a batch of gold with excess nitric so that the gold would dissolve faster - then at the end of the day he would put a button of gold in the beaker on the hot plate over night & in the morning he would drop his gold because over night the gold button used up the free nitric

Keep in mind Harold worked on a VERY large scale & retired VERY well off

I listened to his advice & over the years it served me well

Kurt


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## kurtak (Oct 14, 2019)

snoman701 said:


> My point was that after rar, there are a lot better ways to get your gold back that don’t involve turning nitric acid into NOx.
> 
> For one, just add an excess of silver nitrate. Your gold will drop, albeit contaminated with agcl.
> 
> ...



Per the underlined - now that sounds like a REAL MESS to deal with  :shock: :roll: 

And does it really matter if you create NOx by using up the free acid in an existing solution - or creating it by starting with a new batch of fresh acid :?: 

I think not - NOx it created when metal is dissolved with nitric regardless if it's being dissolved with the free nitric already in a solution or with fresh acid creating a new solution  :shock: :roll: 

Kurt


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## snoman701 (Oct 14, 2019)

In all honesty, if you find gold and silver chloride to be such a “mess”....then your best bet really is just cementing.


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## Chase54 (Dec 11, 2021)

snoman701 said:


> In all honesty, if you find gold and silver chloride to be such a “mess”....then your best bet really is just cementing.
> 
> 
> Sent from my iPhone using Tap


Hi I'm new to the forum and a newbie in refining gold filled watch bands. I have refined karat gold and silver on small scale up to ½Ozt of Au and 4Ozt+Ag however I have been hesitant with these gold filled bands. I have about 1800grams of separated caps that I've been sitting on for a couple years; I would like to get on with refining them. 

I have read about the RAR process however, i don't feel comfortable that I wouldn't just mess it up. unfortunately I don't have cyanide as leaching would be ideal. So my question is what would be the simplist process to do? Should I run 100gr of material, cleaned and lightly incinerated, HN03 dissolve or a 100gr HCl/H2O2 +O2 or both? Thus determine the ease and yield for future runs? Chemicals are not an issue for me and I have experience with lab safety as well as proper safety gear. Please tell me if I'm completely off base or if I'm missing a better way of doing things. 

I bought these band a couple years ago for next to nothing on ebay. I do not recommend messing with them unless they are next to free or brand new. Taking off the caps was the most tedious and disgusting experience I ever went through in regards to refining prep. It is amazing how much skin oil and earwax looking crap can be deposited under those things, I mean it was some seriously disturbing stuff, just be warned. 

Any help or advice would be appreciated.


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## butcher (Dec 11, 2021)

Well, I wasted my time this morning, trying to figure out what you guys decided to name the RAR process, just wait till you have to research the K2BwOS process, or the HGWP process... or any other abbreviation for a word anyone thinks up, it's like texting, I guess you have to be in the loop to understand what it is saying. We have enough trouble with members and different languages, why add new ones or words in an abbreviated code talk, that only a select few understand what you are saying.





RAR abreviation at DuckDuckGo


DuckDuckGo. Privacy, Simplified.




duckduckgo.com





That's my rant, I guess I just need some coffee bad this morning


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## galenrog (Dec 11, 2021)

Which is why I use the phrase “words mean things, so use them properly”.

Time for more coffee.

Edited for spelling.


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## Chase54 (Dec 13, 2021)

I apologize for the cryptic abbreviation-Reverse Aqua Regia (RAR) process. The use of concentrated nitric acid (HNO3) and dilute hydrochloric acid (HCL) to passivate the stainless steel allowing one to selectively dislodge the gold (Au). I have seen the abbreviation many times on this forum and made the the mistake of assuming it obvious. I'm very sorry if I have offended anyone here. My question was sincere and I hope in spite of my poor choice in wording or rather abbreviating, advice might still be forthcoming.


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