# Silver Shotting problem



## Ollie1016 (May 26, 2014)

Hello All,

I am fairly new to refining and PM. 

For the first time, I tried 'shotting' some of my scrap sterling silver into some casting grain(I did use borax). However, after I cleaned the shot with : Baking soda, vinegar and hot soapy water. The silver looked really dirty and horrible. I figured with was because of the copper coming to the surface of the metal. Is this normal? Was I doing anything wrong? Please see attached picture.

All the best,

Ollie


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## Ollie1016 (May 26, 2014)

Sorry, I didn't realise that the picture didn't attach to the original post.


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## butcher (May 26, 2014)

When you re-melt an alloy like sterling silver, you can oxidize some of the metals involved, in this case you most likely oxidized a portion of the copper involved in this alloy.

Conditions of the melt can be change to some degree, to change how much metal is oxidized, but it would be hard to eliminate the problem completely.

This is one reason why an alloy of gold in the jewelry trade is made from scratch, with more pure metals being melted together to make the alloy, With the melting environment controlled as much as possible to keep the oxidation of the easier oxidized metals as low as possible.

Re-melting old jewelry to make new jewelry does not work.
It is easier and better to have the old jewelry refined back to pure metals, and use the more pure metals to make a new alloy for the jewelry.

Re-melting a scrap alloy of gold to make new jewelry is not normally done because of the problem with oxidation in the melt, as well as other contaminates causing problems like lead solder that may be involved that could also ruin the gold for use in jewelry.


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## Ollie1016 (May 28, 2014)

butcher said:


> When you re-melt an alloy like sterling silver, you can oxidize some of the metals involved, in this case you most likely oxidized a portion of the copper involved in this alloy.
> 
> Conditions of the melt can be change to some degree, to change how much metal is oxidized, but it would be hard to eliminate the problem completely.
> 
> ...




Thank you for your reply. I think that I was melting it far too hot. I just melted some yesterday and 'shotted' it. It was 'clean' and didn't have lots of copper residue on the surface. 

I have just found out that my homemade paint can furnace can melt 300g of copper


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