Removing Silver solder from Gold Nuggets

[wct0415]

Hello all
So today is my first day on this board and feel have done a fair amount of studying in watching the videos that I have ordered but by no means can I believe to know much about ant of these refining processes but I do have my first question and it is this.
I recently purchased at an auction a set of sterling silver spoons (6) that have on the end of the handle some natural gold nuggets soldered to them. So my plan is as follows: 1) I am going to remove the nuggets with a MAPP/Oxygen torch to just the point that they will fall of the end of the spoons. 2) Remove the silver solder by taking the advice from those who can lead me in the best method for removing this solder without affecting the gold nuggets. And then proceed with refining the silver spoons to a .999 or better purity.
So what do I know about this process?
I have watched all the video's on Lazersteve's website purchased and watched the Silver refining A to Z video.
I have purchased the following chemicals: Two 2 liter bottles of nitric acid (70%), one 2 liter bottle of Sulfuric acid (70%), on 1 gallon bottle of muratic acid from Lowes, a 2lb bag of borax,
Equipment I have also purchased are 4 ea melting dishes from Steves website the silver anode for the silver cell as well as the anode and cathode from the website for the gold cell. A dozen or so different size beakers and flasks off of EBAY with glass rods and watch glasses my covered Pyrex dish.
So back to my first project, Please feel free to tell me if I am about to go about this wrong, but my thinking since sliver solder melting point is lower than both sterling and gold it should be a easy task to remove the nuggets with the tourch I have mentioned. So my question to the experts is about the best way to remove the silver solder from the gold nuggets.
Second question is what will be my best course of action to refining my sterling spoons given what I have described as what materials and equipment I have listed
Thanks Bill

 

[Fournines]

Cut the end of the handles off, just leaving a bit of the spoon attached to the nugget (get as close to the nugget at you feel comfortable).

Put the nuggets with the small attached pieces into a solution of 50% Nitric and 50% distilled water. This will dissolve your silver, while leaving the nugget untouched (theoretically).

 

[wct0415]

So are you suggesting that removing to nuggets with the torch is not a good idea.

 

[Fournines]

So are you suggesting that removing to nuggets with the torch is not a good idea.

Not that the torch is not a good idea, but just a different way to handle it. You're going to probably have to use nitric anyway to get the solder completely off. Are you trying to save the nuggets in their original form?

If you're going to refine the spoons, you can just put the spoons in their entirety with the nuggets attached into the solution and still achieve the same end result.

How big are the nuggets? If you're planning on refining them, depending on their weight, it might make sense to melt it all together - then you've just inquarted your gold all in one step.

 

[wct0415]

Well I have been told since natural nuggets of a couple grams and larger are rare and carry a premium to refined gold my thinking was to keep then in their natural form. My only concern with putting them in nitric for any long than I must is that if there is any other metals within the nuggets that it may start to remove that also and lessen the weight of the nuggets and make them somewhat porous so to speak. A natural nugget can be anywhere in between 20-24k purity

 

[qst42know]

Where they are soldered has already been altered from the natural form perhaps they have even been filed for a better fit while soldering. I have doubts you will be able to preserve the premium in this case.

 

[manorman]

At todays gold prices one gram nuggets carry very little if any preumium, on e-bay you will get over spot but then you have all the fees.

 

[Drewbie]

To keep the amount of silver solder left on the nuggets to the minimum, you could the trick used when removing components from a PC board - there is a product called "solder wick".

http://en.wikipedia.org/wiki/Desoldering

If you only need to use a small amount, you can make it with the flattened braid from coax cable, soaked in flux.

 

[qst42know]

Solder wick works fine for tin lead low temp solders, but joining gold and silver is usually accomplished with what should be called a brazing alloy. A fine copper braid would be consumed into the braze at melt temperatures.

 

[Harold_V]

Solder wick works fine for tin lead low temp solders, but joining gold and silver is usually accomplished with what should be called a brazing alloy. A fine copper braid would be consumed into the braze at melt temperatures.

True, and silver solder is readily dissolved in dilute nitric, so there's not much of an advantage in even trying to minimize the amount of solder ---right down to clipping the pieces and dissolving the sterling and the solder. Assuming the nuggets are of high quality, they may not experience anything more than a good cleaning. I would expect that soldering them will have introduced more change than cleaning with acid.

Harold