Re: Removing baked enamel from coin

"richard schumacher" <no-spam@xxxxxxxxxxx> wrote in message
> In article <f0Scf.7389$m81.4952@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
> "Jonathan_ATC" <replytome@xxxxxxxxxxxx> wrote:
> > If it is "real" enamel, which is kiln-fired glass, laquer thinner won't
> > work.
> > To remove real enamel, one would have to suspend the coin vertically and
> > fire in a kiln until the enamel ran off the coin. But, I doubt the OP
> > access to a kiln to do this.
> What is the melting point of 90/10 Au/Ag alloy? How does that compare
> to kiln firing temperatures?
> > That said, it could be the same kind of coloring you experienced,
> > epoxy resin. This COULD be removed by soaking in laquer thinner.

I am a metalsmith as a hobby. I have not worked much in enamel, so last
night at one of our get-togethers I asked some folks who work in enamel for
a living.
Yes, you can suspend the coin in a kiln and heat it to the melting point of
the enamel and it will just drip right off. Just wanted to clear that up
because it was said that would not work. If it is epoxy resin, it will just
burn off.
That said, I was told that the better way was what was described here, heat
it with a torch and quench it and the enamel will pop right off.

As for melting points of silver and coin silver:
Metal Symbol Melting Point ºF Melting Point ºC Specific Gravity Weight in
Troy Ozs/Cu In
Silver, Pure Ag 1761 961 10.49 5.525
Silver, Sterling - 1640 893 10.36 5.457
Silver, Coin - 1615 879 10.31 5.430

That said, most people enamel on Fine silver as it has the higher melting
point. The melting points of various enamel powders vary some by color due
to the additives used to make the colors. However, we know that the enamels
will melt and flow at temperatures lower than .999, .925 & .900 silver
because we've all seen finely enamelled coins.
One such example of these enamelled coins is in the Stacks "The Atlanta
Sale" catalog.

For explanations of different types of enamel and how they are adherred to
coins or other metal, see this site:

I spent 3 hours last night discussing jewelry and coin enamel with people
who do it for a living. Very interesting evening.