Newby Silver smelter here!!

[Rod Triplett]

Hello my name is Rod Triplett and have owned several pawnshops over the last 32 years. I have always just sent my scrap to refiners and gotten paid. Now I am more interested in smelting my own and possibly getting into the refining area. So just learning, making mistakes and hoping to get some help on this chat room. I have just purchased a furnace that goes to 2200f and have done 3 pours now. All of my education has come from youtube and have learned a lot in just three pours. The only thing I have smelted so far was silver quarters (don't worry they were all worthless as coins.) My biggest issue right now are these huge craters on both sides of the bar. What is causing these? I am looking forward to reading these posts and learning how to smelt professionally!!

 

[FrugalRefiner]

Welcome to the forum. The subject of pawn shops comes up often here, so I'll look forward to hearing your views.

You're not smelting your metal, you're melting it. Melting is heating solids till they become liquid. Smelting does the same, but it includes adding other chemicals to bring about chemical changes in the melt. For help on terminology, see A Glossary of Common Terms.

While the coins had no collector value, they are self-assaying. Everyone knows the silver content of US coins. No one knows the silver content of your bars. I'm sure you deal with the same issue in your shops. How do you deal with it, and how does it affect the prices you pay?

Much of your irregular surface comes from oxygen that is absorbed into the silver when it is molten. It can actually absorb many times its volume of oxygen. When the molten silver cools, the oxygen gasses out. Pouring nice silver bars is an art.

Dave

 

[Rod Triplett]

Thanks Dave i appreciate the response. Yes I realize the coin to bar issue but these will probably just go to my refiner when I send in my other silver. They will assay it all and pay me for what ever it comes out to. I was just using these coins to "play" and "learn" with. Thanks for the terminology clarification. How do I rectify the oxygen absorption? What is my next step? Thanks Rod

 

[FrugalRefiner]

So, when you buy, how much does it affect the prices you pay.

You need to keep the oxygen away from the silver. Reducing flames in gas furnaces lessen the oxygen that can be absorbed. Carbon covers or inert gasses can be used to shield the melt or consume any oxygen that gets close. Preheating and sooting the mold. Puring into a book mold instead of an open mold. Keeping a reducing flame on the mold till the metal freezes. And probably a lot of others that aren't coming immediately to mind.

There should be a lot of good threads in the Silver section that will cover it in a lot more detail.

Dave