# Silver Plate



## Buzz (Sep 17, 2009)

I stumbled across 4 Silver Plated dinner forks in my shed earlier today.

I placed one into a jar of 70% Nitric, just to see how long it would take to dissolve the plate.

Not very long as you'd guess.

When the plate had gone, underneath it was a snow white layer of something.
I left it in the jar a bit longer to see what would happen and sure enough the acid
burned right through this layer and started to dissolve the base metal.
It seems the white layer has gone into solution too.

What would this layer be?

Regards
Buzz


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## metatp (Sep 17, 2009)

It could be nickel or a nickel/coppe alloy. Did it turn the solution blue?


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## Buzz (Sep 17, 2009)

Solution turned a clear dark green colour.


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## qst42know (Sep 17, 2009)

Silver plate flatware is usually over brass, or more commonly an alloy of copper, nickel, and zinc, called nickel silver or German silver.

Perhaps the silver in solution was reacting with the zinc content until it was consumed from the surface.


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## metatp (Sep 17, 2009)

Is it a very dark green that is hard to see through. I guess that may depend on how much nitric and water you used. I had a mixture with brass that reacted the same way. It also contained nickel. I had 134g that yielded less than 2 grams of silver.


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## Buzz (Sep 18, 2009)

Yes, it is dark green but hard to see through.

I wasn't really looking to recover the silver, just wanted to see
what kind of reaction i got and to see if i could figure out
what the base metal is/was.

It was just Nitric i used as i have run out of distilled water.

Buzz


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## metatp (Sep 18, 2009)

Did you have a chance to get a good look at the metal after dissolving somewhat in nitric? The metal I had was a silver color. I added just enough nitric acid to dissolve it if it were pure silver. It was not enough for the mistery metal. After a day of sitting and no more reaction, I removed the leftover metal. It was brass in color.

Also, the reaction in nitric with 50% water was very fast. A lot faster than a chunk of silver.


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## Buzz (Sep 18, 2009)

The colour underneath the silver plate was white and under that it was a brassy copper colour.
A mystery to me too!

Buzz


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## Platdigger (Sep 18, 2009)

GSP, were are you? 8) 
My guess is he will know what metal was plated over the copper (or brass), before the silver.


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## qst42know (Sep 18, 2009)

I don't recall ever finding a piece of plated copper flatware, plates and bowls and vases, yes, but not spoons or forks. Copper would be to soft.

Zinc content the most reactive being attacked first by the acid gave the colors you saw I would imagine. A better indicator of the base metal would be a good stroke with a file.


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## lunker (Sep 22, 2009)

What were the markings on the back of the peice?

EPNS is electro plated nickle silver. a composition of 60% Cu 20% Ni 15%Zn 5%Sn It is far more valuble to a scrap dealer due to it's high nickle content.price will be slightly higher than 312 stainless.
If it says "India" it is typically plated brass
"rogers bros" " Xtra" and similar logo's Can be a mix of german silver, Brass and in the rare occasion copper.Copper will usually be marked EP copper etc. I sell it all as dirty copper.
There is also silver plated lead on some salt shakers etc.I have never come across anything real exciting but i am always hoping!


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## Buzz (Sep 23, 2009)

It was just your bog standard EPNS.

The solution has been standing about a week now and i've noticed salts forming
at the bottom of the jar.


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