I am looking at a good deal on a fair amount of GF watchbands and was wondering the best way to tackle this.AP for a few days or straight to Nitric or electrolisis.Haven't found much in here on watchbands so was asking for some advice.Any would be deeply appreciated
GF watchbands
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Irons
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"..at least one is Gold filled."
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I used to strip them with an electrical cyanide cell. Cathode was a sheet of 300 series stainless. Bands were placed in a non-conductive basket that was suspended about an inch from the cathode. Stripped metal, consisting of copper, gold and silver, formed a solid coating on the stainless, which was removable by scraping with a razor. Bands were submersed almost to the top, where I'd use a piece of titanium as an electrical connector. It was desirable for the titanium to not be submersed. It was simply placed on top of the bands, which were dumped and reloaded a few times to insure that all gold was exposed and stripped. Not a fast way to recover the values, but trouble free, and not labor intensive.brjook said:
Harold
qst42know
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Far superior to digesting all in AR and using copper based GF to cement. It works but the resulting iron nickel syrup is truely a pain to wash out of the cemented values. It is hard not to lose some in the dark inky blue solution.
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There's one advantage to processing watch bands that is often overlooked. The vast majority of their construction is stainless steel, which is not dissolved by nitric. You may be able to process by a nitric digest, which will eliminate non-ferrous materials, leaving the gold behind. Problem then is to separate the gold from the stainless. It will be trapped in all kinds of ways, so that may not be as easy is it sounds.
By applying AR carefully, you may be able to reduce the amount of stainless that remains with the values. Less than would be required to dissolve everything is applied. Values dissolve, then then they are cemented on the stainless, dissolving the stainless in the process. When no values are detected by testing with stannous chloride, the solution is siphoned and the process repeated. When just traces of stainless remain, everything is dissolved and processed for recovery of values. It requires patience, due to the slowed recovery of values as the stainless diminishes in volume. By this process, the vast majority of contamination is removed, yielding a better quality of gold, and from a reduced volume of solution.
Alternately, you can pick off the gold filled pieces, discarding the stainless. That works perfectly well, but you must look at your time as having no value. Fine for the hobby refiner, but certainly a losing proposition for the guy that values his time. Watch bands tend to be a rather poor source of gold (but still worth processing).
Should you make a decision to process by acid, make damned sure you incinerate the watch bands. You'll come to understand they are filthy---loaded with soap scum and body oils.
Harold
By applying AR carefully, you may be able to reduce the amount of stainless that remains with the values. Less than would be required to dissolve everything is applied. Values dissolve, then then they are cemented on the stainless, dissolving the stainless in the process. When no values are detected by testing with stannous chloride, the solution is siphoned and the process repeated. When just traces of stainless remain, everything is dissolved and processed for recovery of values. It requires patience, due to the slowed recovery of values as the stainless diminishes in volume. By this process, the vast majority of contamination is removed, yielding a better quality of gold, and from a reduced volume of solution.
Alternately, you can pick off the gold filled pieces, discarding the stainless. That works perfectly well, but you must look at your time as having no value. Fine for the hobby refiner, but certainly a losing proposition for the guy that values his time. Watch bands tend to be a rather poor source of gold (but still worth processing).
Should you make a decision to process by acid, make damned sure you incinerate the watch bands. You'll come to understand they are filthy---loaded with soap scum and body oils.
Harold
goldenchild
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Harold_V said:
I suppose watchbands being a poor source of gold is relative to how much gold one recovers. Watchbands happen to be my favorite source of gold after karated. I would go as far as to say they are my bread and butter. I simply pluck the caps and digest in nitric leaving behind the foils. You will save gallons of nitric plucking caps opposed to putting the bands in nitric straight away.
Harold is 110% correct about incineration. Out of the hundreds of pounds of watchbands that I have scrapped over the years, only a few pounds were brand new. The rest had soap scum, body oils, various dirts and cruds and... gulp... hair :-X Make sure to wear gloves and a mask when plucking the caps and incinerate well. If not you will have a nasty molasses like gook clogging your filters which you will have to incinerate anyhow or trail along in the following processes.
An H2SO4 cell may also be an option.
You guys are the Bomb and Harold your thr Guru of the site .What you say is the gospel.Golden what do you mean when you say pluck the tops.Will the GF come off the substate or you are talking about the pins and maybe springs?
Hey i am takeing every word you all say to heart and again deeply appreciat all of your time and advice.
Hey i am takeing every word you all say to heart and again deeply appreciat all of your time and advice.
goldenchild
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samuel-a said:
Yes. Literally pry them off the band. A needle nose pliar works great for me. Here is a little 140 gram bag.
Be aware however that there are bands that contain silver and I'm not talkin' plated. These bands contain solid sterling silver. They are pretty rare though. Both the bottom and top caps are made of sterling silver. I can always spot them right away. They always seem to have a rose gold like hugh and of the same design. And there are some super rare ones that are 100% sterling except for those tiny springs used for expansion. I have only ever found three of these and they were in the same batch. They yeiled about an ounce of sterling each. Oh how I wish I would have taken pictures.
Below is not a silver bearing band but shares the same design.
While writing this I remember that I have found one other band that did not share this design. So you're probably wondering now how will I ever know which are silver and which aren't? :lol: Dont go scratch testing every band. The dead give away will be that the caps are super soft when trying to pry them off. It will be like lead compared to the hard stainless/aluminum caps.
samuel-a
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goldenchild said:
On my very first batch of GF band cap i had 2 or 3 of those, yes, they ware rose colored with the same designe you show here.
Needles to say how surprised i was to find almost an ounce of silver out of that first batch...
goldenchild
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samuel-a said:
You saying this sparked another thought. A hard lesson learned in fact. If you do find any of these bands... process them SEPARATELY! If you leave them in with the other caps you will create a very big head ache for yourself. What will happen is the silver will dissolve and immediately cement out. This will go on until all base metals are dissolved. Needless to say this wastes much more nitric than you would have calculated for a non silver bearing batch. I still get caught with this sometimes on other batches of GF scrap where silver is undetectable. Another good reason to keep your digestion batches small.
On the bands they say 12k GF .Does this mean the caps are solid 12k or just a thick coating on them.When i dissolve in nitric there is alot of reaction and red smoke.I figured if they where 12k they would react slower and as they dissolved all that was left was a thin film of gold.Any advice before i make a mistake and lose alot of gold.
qst42know
Well-known member
12k GF means "1/20th of the original weight is 12k", just the tops on some, all on the outside surface, and subject to all the wear losses.
If the "gold filled" karat and fraction are not specified it is assumed to be 1/20th 10k.
If the "gold filled" karat and fraction are not specified it is assumed to be 1/20th 10k.
