Silver solder

Originally Posted by AuburnEwaste

In with some other junk I picked up today I found a couple boxes of lead free solder. Does anyone know if there is a market for this stuff? Most of it is scrap, but there are some un-opened canisters, though they are expired. I have about 55lbs of it.

It is 96.5% Tin, 3% Silver, and .05% Copper. I did some math and it comes out to just over 24 troy ounces of Silver.

I am glad to see that you figured for troy ounces, and did so correctly.

Please keep these things in mind when thinking about how much real value you have in the silver, and what you can get for it. It's worth, about, at today's sport prices around $385.00 - $386.00. A refiner has to factor in the cost of processing this type of material, and for myself I try to make at least 30% profit on anything I process to cover my time/labor and to make a small, reasonable profit so I can continue my work.

Solder with Silver alloys are not nearly as easy to process as other types of silver alloys. Tin creates a problem, if not processed correctly. Tin Oxide is very difficult to filter, so material like this is usually melted, and then processed in a Balbach-Thum or Moebius electrolytic cell, which requires melting the material into a bar or bars, and then processing in a vat filled with an acid solution. This requires energy (gas and oxygen) to melt the material, which also incurs a melt loss of a small percentage of the metal being melted. Because the material is considered "dirty", being that the Ag (silver) content is so low, a second refining is required to obtain high purity.

I am all for recycling any type of alloys that have values worth recovering, but often I pass on material just simply because the person selling it asks too much, and rarely wishes to negotiate a price where everyone can make a reasonable profit. Just shipping 55 lbs takes a nice big bite out of the profit. I don't have a problem at all with people who try to make as much off the material they work so hard to obtain, but too often there is no consideration as to how the refiner will recover their investment and make a small profit.

I would store the solder for now, and wait until you have a larger quantity to sell. In that way, you can cut down on some of the overhead making the material more valuable. If for example you were to find a silver solder alloy that was much higher in silver content, it allows the material to be processed if done all together, one time in a silver cell to be of high enough purity that it will not require a second refining. Also, when "dirty" silver is processed in a electrolytic cell, the solution is dirty, and must be processed also so that the "dirty" solution can then be replaced with a solution of only silver nitrate so that the cell can then be used again. This can be expensive as it adds an entirely different process to refining that otherwise could have been avoided.

Scott