"chaniarts" wrote in message
...
Harold & Susan Vordos wrote:
"chaniarts" wrote in message
...
RBnDFW wrote:
Harold & Susan Vordos wrote:

Gold should never be melted in any kind of metallic vessel. Molten
metals are strong solvents of other metals, so the gold
will be contaminated, often rendering it useless as it loses its
ductility, depending on the alloying element.

so, if I wanted to melt a few old rings down into a cube or ingot,
what vessel or mold material can one use?

ceramics


That can be risky. What ever the choice may be, it must be
resistant to thermal shock. Ceramics (Coors, for example) isn't. My
previous post details what works very well, and has been used for
years by the jewelry trade. I used the same system when I refined
small lots.
Harold

your next post states:

"My recommendation is to go to a jewelry supply store and purchase a
melting
dish. They are made of clay, and not terribly expensive. It is VERY
important that you season the dish before using."

tmk, clay is ceramics.

I know and understand that, but if you say ceramics and leave it as such, I
think you'll find that enough people will not consider a clay dish as being
satisfactory, when it is, and may even consider that Coors lab ware would be
the best choice. If you've ever worked with any of that stuff, you know
how it isn't fond of thermal shock, which is hard to avoid when working with
molten metals.

Harold