Dental Gold

Hi Charles, Think about the question. If it would be dangerous
to remelt these golds would it not be just as dangerous to melt
and cast it the first time? There are no caveats on the gold
packages. The majority of the metals are gold, platinum,
palladium, silver, indium, gallium(sp?) and copper. The only
thing that I know about that could be harmful is melting old
dental amalgam with its mercury content. I hope that this helps.
Regards,

Skip

Hi Rob and Char,

First let me thank you for your kind thoughts.

The ‘silver’ is probably silver amalgam, a mixture of silver and
mercury. This is the self-same mercury that made the hat makers
of the 16th, 17th, 18th, and the 19th centuries looney! The
best thing is to include it into the scrap you send to the
refiner.

As for the ‘teeth’, if they have porcelain on them, they could
be anywhere from base metal to 90% gold or a palladium/silver,
or palladium/3-5% gold alloy. If the 'teeth are all gold they
could be anything from a brass/aluminum alloy (very light
weight) to 80% gold. Usually the higher % golds are very yellow
and somewhat softer. If the ‘teeth’ apparently made from sheet
stock with either a swedged or cast chewing surface they are
22kt. around the band and 18kt, on the chewing surface. I am
sorry that I can’t be of more help.

Warmest Regards,

Skip

Skip Meister
@Skip_Meister
Orchid Jewelry Listserve Member
N.R.A. Endowment &
Certified Instructor
in all disciplines
Certified Illinois D.N.R.
Hunter Ed, Instructor
ICQ 37319071

It may sound like an odd question (as I did search the achieves with
no results), but here goes: Can one melt down the gold from a large
old gold filling and reuse in jewelry applications? I just discovered
that - for reasons unknown - my husband has kept a tooth with a huge
gold cap for more than 35 years. If the gold is useable, how would
one go about dealing with the tooth itself?

This subject is a bit macabre to me at least but with the price of
gold today, I’d like to know the answer. Can anyone help?

Susan

The sliding weight tool with a sharp hook on it, ask the local
dentist about them. The ones used for car dents is a little too big.
You can probably make one that will last for a time or time of use.

Jerry

Susan,

Not macabre at all. I have made a number of beautiful pieces using
dental gold. One has to be sure the gold is well cleaned before
casting it or making it into an ingot for rolling out. In fact, I
found it quite easy to work with and it has a great color. Go for
it!

Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry! @coralnut2

Susan,

I have burned out teeth to salvage the gold. Worked fine for me. The
surrounding material will burn off in the crucible. May smell a bit,
but leaves the molten gold behind. Use borax to clean and pour into
your ingot.

Terrie

Susan,

Dental gold actually is great for casting. Make sure you get all the
old tooth and any glue that is inside the tooth cleaned out
completely. Sometimes soaking in acetone will do the trick of
releasing the tooth. If this doesn’t work then you need to break the
tooth with heavy pliers or a hammer. After the tooth is removed soak
it in acetone again to remove as much residue as possible and if
needed use your flexshaft with a bur to finish cleaning the inside.

Greg DeMark
email: greg@demarkjewelry.com
Website: http://www.demarkjewelry.com
Custom Jewelry - Handmade Jewelry - Antique Jewelry

Really old dental gold was around 18K and would cast easily. The
newer stuff is alloyed for hardness, its brittle and doesn’t look so
good. I would mix in some clean scrap like an old chain to give it a
richer look. As for the teeth, I put them in a plastic bag and hammer
away. There will also be some glue residue to scrape off. Or you can
put them in your scrap box an send them off to the refiner with your
next batch. ( the easy way).

Chris

of course you can reuse the Au. Just a few words of caution. first,
try to remove all the old amalgam or anything that loks like it isnot
gold before putting it in your crucible.Then, most dental gold is at
least 22kt., you may wbnt to get out your test needle and test for
the exact karat, then if you have other scrap and want to stretch
your “bounty”, you can have a higher quantity of say 14kt. to work
with…if alloying, use .999 silver, pure copper, and if you require
white gold, nickel or palladium alloy and you can make any colour you
desire…if you need more info, the jewelers handbook, tim mccreights
"complete metalsmith pro ", oppi untracht’s, and carles codina’s
books all have karating tables, as does the Rio grande catalogue
(please understand thatis neither a pro or con endorsement of rio’s
products). If you wish to convert your dental gold into blue or
purple, the process is a bit different, and despite what some folks
in Orchid proferr, it can be done without the most expensive
equipment on the planet,( i would be happy to share my ancient
technique for alloying purple AuA12 if that’s what you really
want…with my process you won’t be left with bits of purple gold only
suitable for inlaying either…) otherwise for a beginner, yellow,
rose/red, green or white gold should provide you with enogh
choices). so melt it down sister!

Can one melt down the gold from a large old gold filling and reuse
in jewelry applications? 

Dentists use various types of gold alloys to achieve their
objectives. There are some strange metals that wind up in dental gold
to make them super hard to resist deformation and resistance to great
pressure from chewing. Also, the gold can come in different karat
content, usually in the 9kt.-12kt. range. Dentists send their gold to
refiners that specialize in recovering gold from dental procedures.
You might talk to your dentist or see if there’s a local dental
supplier who knows of a dental refiner. To get the tooth out, just
smack it with a hammer on the tooth side. Goggles and mask, to be on
the safe side.

On a similar note, when my brother-in-law passed away, my sister,
bless her heart, gave me the job of going through his teaching
models and pulling out the gold. After sending it to the refiners,
she recovered a little more than $2,000 from refining, paying the
refining charges inclusive. Some were yellow gold, some white with
palladium and platinum. It was a nice little windfall.

Once and only once, I recast dental gold for a clients custom order.
I cast it much hotter than normal as I was told from another dentist
client that it most likely had palladium in it. Once cast, it was a
challenge to polish and very challenging to set stones into. It felt
like 18k nickel white to me. I would not do it again. The labor to
fill unusual pits, set stones without breaking them, the need to
segregate and cast it alone and isolate all the filings, was not
worth it to me or my client…who paid a much higher labor rate for
all this extra care! (And, the gross-out factor was really high too)

Working with elk teeth…another thing I wont do again! Smelly stuff
that’s probably toxic when airborne?

Ahhh, the adventures of a custom metalsmith.

T Lee

T Lee Fine Designer Jewelry
18 University Ave NE
Minneapolis, MN 55413
(612) 789-2656
(612) 677-3700 fax

Dental gold often contains Platinum, and or other platinum group
metals, it is often about 16Karat approximatley 66% pure
gold, but the other metals may or may not give you the working
properties you are looking for…

Before you put a torch to it put the tooth in a plastic baggie and
smack it with a hammer to get rid of as much of the tooth as
possible. The baggie will stop most of the tooth from flying around
the room.

Then melt it in a crucible. Less tooth burning is less smell.

Dental gold varies in both karat and alloying materials. It is
engineered, since the 60’s I would think, to cast well, with minimal
shrinkage and with a “micro refined” grain structure. This refined
grain structure yields a dense casting that is less prone to pitting
and brittleness.

When I made crowns and bridges years ago, the dentists sometimes
specified gold occlusal surfaces–the biting surface-- for crowns
such as molars that would recieve porcelain on their facial or buccal
surfaces, since gold, while perhaps cosmetically less appealing than
tooth- like porcelain (this was before the age of bling), was kinder
to the opposing dentition and so less likely to wear the upper or
lower molar down.

The mouth is a pretty hostile environment to metals. Saliva can act
as an electrolyte or even a mild etchant. Castings that had shrink
spot porosity or spongy structure quickly discolored and became
bacterial traps.

Many of the yellow gold alloys that I worked with were somewhere in
the 16k range. Many of the alloys did, indeed, contain palladium.
(Although I can’t recall the casting temp. to be much higher than
similar jewelry alloys.) Different alloys were engineered for
different applications. Alloys designed for use with certain types of
bridgework were rigid and stiff, the better to hold any porcelain
that might be applied to the surface. Full coverage gold crowns were
cast in gold that was fairly “noble” and non reactive with malleable
margins (the thin place where the crown met the remaining tooth prep)
that could be burnished down to seal the crown against saliva and
bacteria.

So, all dental golds are not created equal. One thing to remember is
that all metals in the mouth are not necessarily gold. Any white
metal I would look on with suspicion. Porcelain single crowns that
are built around a white metal coping may be a special nonprecious
alloy that may contain chrome, etc.

I have recast and even rolled down yellow dental gold in the past
without many problems. It all depends on what the alloy is. One thing
to consider is if you have enough gold to include a button and
sprues. I had a reserve of mystery gold of similar karat that I would
use to make up the weight for any gating, etc. I didn’t like to
consign any of my “known” gold alloys to the mystery melt.

Good luck and give it a try.

Take care,
Andy Cooperman

i would be happy to share my ancient technique for alloying purple
AuA12 if that's what you really want.. 

I would certainly like you to share the technique. Thank you very
much for the offer.

James S. Duncan, G.G.
James in SoFL

Speaking as a Dentist:

There are many different gold alloys used, depending on the
situation. The alloys are all different colors and different melting
points and melting characteristics.

You already have good advise regarding removing tooth structure and
amalgam (super important: mercury vapor is very toxic). If you would
like to cast something, sort by color is the best advise I can give
you. You will never know what Karat it represents unless you test.
It works well for models that you want to keep around without
investing a lot in the metal. Bottom line is send it to a refiner.

Charles Friedman DDS
Ventura by the Sea
Prosthodontist, wood turner, metal spinner

i would be happy to share my ancient technique for alloying
purple AuA12 if that's what you really want..with my process you
won't be left with bits of purple gold only suitable for inlaying
either..

Please share your method with us.

James Binnion
@James_Binnion
James Binnion Metal Arts

360-756-6550