Greetings Casters,
I have used the lost wax process to cast silver and yellow gold but
never white gold. Now my wife would like a white gold ring. I can pay
a local jeweler to do the casting but since I have a centrifugal
casting machine and the related equipment I would rather do it myself.
Should my experience with silver and yellow gold be enough?
Thanks,
Eric
Get thee to one of the Yahoo "castinghobby" groups . I think there is one
oriented towards what you're doing . I'm into lost foam aluminum castings
right now myself ...
But from my limited (very !) casting , it appears you have the experience
and equipment , worst that can happen is you'll get to melt it down and try
again ...
Having refined gold for many years, the worst thing that can happen is that
the alloy is ruined in melting, yielding castings with porosity. An
oxidizing flame should be avoided.
Casting white gold when it is alloyed with nickel can be difficult, so
careful heating is in order. If the gold is not new, you risk including
silver with the alloy, which will not be in your best interest. Make
certain that no solder is included in the melt if at all possible. That can
be a source of silver.
For those that think white gold is white because it contains silver-----that
is not the case. Gold alloyed with silver yields green gold, not white.
White gold is an alloy of gold and either nickel or palladium. Nickel is
most common.
Harold
Heh! It sure can be. Dental gold, assuming that's what you have, is not
only high in gold (you can safely assume 16 karat in most cases), but is
also alloyed with palladium and platinum. All depends on the nature of the
gold (how it was used in the mouth can make a difference in the alloy. There
are many dental alloys, not just a few), and when it was put in service.
When gold hit over $800 back in '80, many of the providers of alloys
introduced low gold content materials to curb the cost. Therefore there's
no guarantee that what you have will be of high value, but know that of all
the scrap varieties out there, aside from gold coinage, nothing yields
greater values than dental scrap. It was a favorite of mine, and a
wonderful source of the platinum metals.
You might try to determine the specific gravity of the material you have.
If it's high in gold, it will show by it's weight. Both platinum and gold
are exceedingly heavy, gold about 50% heavier than lead, and platinum about
10% heavier than gold. Dental gold of high gold content, therefore, is
generally unusually heavy.
If you had the desire, I could instruct you on processing them, but it's
rather involved for a guy that doesn't understand refining, and requires
nitric acid, which borders on the impossible to buy these days.
Ask if you're interested.
Harold
I'd not be interested in any processing but I can get any chemistry I want
from a cousin in the business. I was wondering if I should sell it now. It
is very old, probably from the '40s. Where would I sell it?
Indications are guys are getting greater than real value from sales off
ebay. It would help for me to see what you have, so I could give you
better advice. If you'd like to send me a picture, my address is
correct.
I co-moderate a forum for precious metal refining. If nothing else, you
could offer it there. Many of these guys are willing to buy, but at a
price that permits them to refine the material. Don't expect full value
unless you can swing an ebay deal. You may be pleasantly surprised at the
selling price.
If you take it to any of the typical gold buyers that advertise, you're
likely to be paid substantially under value.
Harold
Thanks, I will attempt to remember where I put all my jewelry making stuff
and photo and weigh the gold. It will never be used for a project as I had
imagined, sadly.
On Sun, 28 Dec 2008 21:29:14 GMT, "Harold and Susan Vordos"
Greetings Harold,
Thanks for the reply and the advice. I will be using white gold
casting grain. So it will be new. I know about using old stuff and
porosity.
Snag,
I will check the yahoo groups, thanks. Lost foam casting has
interested me for a while. Are you doing this at home? Having much
success? I have looked into having some stuff cast using lost foam
because of the potential for good surface finish on the parts. Is this
your experience?
Cheers,
Eric
I'm doing it in my back yard , and I'm a rank newby . If I took the time
to properly finish a foam core , I'd get a lot better surface finish . That
involves painting a film of thinned drywall mud on , letting it dry
thouroughly , times three ... I get impatient , bury the bare foam in sand .
And the finish shows it . I'm machining most of them , so it's not always
important .
If you get on the group I'm on (
http://groups.yahoo.com/group/castinghobby/ ) I have some pics of the two
castings I've made so far in the "Snag's Castings" photo album .
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