I know I’m not putting this the right way, but when used jewelry is recycled is 14k gold usually just melted and re-shaped into more 14k gold, or do they ever separate out the impurities and re-mix it into, say, 18k gold or 24k gold?
If it isn’t done, is it due to technical difficulty, high cost, lack of demand for the purer product, or something else?
Just wondering.
Most refineries melt all the gold that comes in, remove the purities, and wind up with 24K(pure) gold, which is then custom mixed to make whatever karat the customer wants. In the US, it’s usually 10K, 14K, sometimes 18K. In the Far East, it’s usuall 22K or 24K.
Thanks! It’s nice to know that crappy US gold can aspire to something higher in the afterlife.
Note that the ‘impurities’ mixed in to make the gold are things like copper, zinc, silver, palladium, nickel, rhodium, etc. These metals are also valuable in themself, so they will often be recovered and re-used, too.
Alright, I have a fair amount of scrap silver and gold. Can I refine it myself pretty easily? Buy some coal and a pot or something? How much should I expect to pay a professional to do this for me? For argument’s sake let’s say I have about 8lbs of sterling silver and 12oz of scrap gold jewelry that’s probably 14karat
Nickel and zinc do not have nearly the value of the others. Copper is actually affordable enough to make pipes from it, and silver is not all that rare. Rhodium I can’t speak to the value of. Palladium and platinum are more valuable than gold.
“Valuable” doesn’t necessarily mean as a precious metal. Copper is apparently worth enough that copper wire and pipes frequently get stolen off of construction sites, to be resold.
Rhodium is currently about $1500/ounce US. Platinum is currently about $1275/ounce US.
Palladium is about $300/ounce US. Gold is $1000/ounce US.
Palladium did get as high as $1000/ounce a few years back when the miners in Russia refused to work and the government stopped selling palladium. Platinum got up to over $2000/ounce a few years ago. Gold is essentially at an all time high. Rhodium, in 2008, was at an astronomical $10,000/ounce US!!!
Thank you Samclem, my ignorance is fought. Again.
Bueller? Bueller?
When I was a kid, I babysat for a family. The dad would melt sterling silver silverware in the backyard. Turns out that he was a burglar and this was one way he was able to get rid of the stolen goods. He poured the molten silver into a mold and made cubes of silver.
I am not dealing with pure silver or gold, it’s mostly sterling and 14-18 karat, respectively, so I don’t think the melting route will go well?? At least that’s what I’ve gathered from some cursory google queries. I would have thought I could just melt everything and eventually it would crack itself out but that just goes to show how little I know about this stuff 
I’ve delved into Google a bit more for refining and it looks like for gold I will need some hydrochloric and nitric acids to dissolve the metals and then filter them to get it out. Seems I can go the same route for silver but the details are not quite as clear.
All in all, it appears like the homejob it might be more trouble than it’s worth for the relatively meager amount of metal I have, so I do wonder how much it would cost to have a private party do it for me. I called a couple local jewelers and they just wanted to buy the scrap.
Several of our local Parks have kilns used for firing ceramic pottery – would something like that get hot enough to melt down jewelery?
Depends. Firing temperatures used for decorative low fire ceramics or glazing, which may be the sort of thing you are talking about - silver, maybe, gold, no. Higher fired ceramics, like stoneware - yes.
The melting point of gold is 1947 degrees F, which somewhere around cone 04 to cone 02:
http://www.bigceramicstore.com/Information/ConeChart.html
Silver has a lower melting point, 1763 F.
I’m not sure what your question is. Why do you want to do this yourself? What’s your objective?
I have some scrap gold and silver jewelry. I would like pure(r) gold and silver, preferably in a form resembling an ingot.
A thread on another site outlines a few approaches (especially 4th post down). However you would be very wise to consider using a specialty metal smelter or refiner instead. You do not want to handle corrosive acids and molten metals without suitable experience, equipment and a safe operating environment. Handling aqua regia is particularly dangerous, given its highly corrosive nature and the toxic NO[sub]2[/sub] fumes it emits.
Yeah, that link was already grayed, I think it was this after reading this one I decided that the “do it at home” might be a bit over my head. I mean, it seems pretty straightforward (a couple others have reference pictures) but yeah, we are talking about some pretty serious hazmat shit right here.
So how much would a professional charge? Any ideas there? Do they charge by the job? By the weight of raw or finished material?
No idea as to a ballpark figure for recovery cost I’m afraid, never having owned such precious metals. I’d suggest your best bet would be to Google something along the lines of ‘precious metal refiners’, ring up a local company for a quote, and then compare that with the price you would receive simply from selling it as is to a gold purchaser, or through ebay. Luckily for you both gold and silver are well priced due to the credit crunch, but with some form of recovery on the horizon, now would not be an unwise time to sell, at least in terms of the short to medium term.