Hello,
I recently had a customer come in to sell their scrap metal and sold
off a small hand-forged bowl with a spout. They said that it was
platinum and the shop manager bought it at scrap value as he cannot
figure out what else it could be. It is not stamped with the typical
marks; it has 505 on it and also, APW, with the letters sort of
combined. The man said that his father worked for the Manhattan
Project and it was used as a crucible for engineering a bomb. Anyway,
I was interested in buying the bowl for scrap value from the store
because I think that it is worth more than scrap and is (maybe) a
piece of history. Any idea what these stamps could mean? I cannot
find anything with a google search. Also, I have a tiny amount of
doubt that is is actually platinum. It has a small amount of memory
to it when you flex the paper-thin rim, which seems unlike platinum.
However given a little bit more pressure, it bends and stays. It is
heavy for its size (32 dwt)and the size of a large orange. It heats
up white hot without melting, does not discolor or tarnish (like
PD),files just like PT, and does not react to acid tests. When tested
with the GT-4000, it tests in a range higher than 18k, but not into
the Plat category. Anyone have any idea if this actually
characteristic of PT and what those stamps might mean?
Thanks in advance!
Megan
Megan:
The Manhattan project is something of a hobby of mine. I don’t
recognize those marks, but the only thing I can think they might
have been using a Pt crucible for is some of the early micro
chemical work on U235 and Plutonium. Neither of these are things you
really want to be dealing with, even in residue.
Step 1: wrap it in lead foil, and leave it there until you can find
someone with a working geiger counter. Lacking lead foil, dunk it in
a fish tank. Water’s a good moderator.
If memory serves, plutonium is mostly an alpha emitter, and that’s
easily stopped. I’d suggest talking to the local university’s chem
department. Explain what you’ve got, and that you’d very much like
to have someone with a calibrated geiger counter check the thing
over. Once you’re sure it’s cold, then you can play with it till
the cows come home. I know Los Alamos has a historian, I’d suggest
contacting him, to see if (A) he knows what it is, and (B) if it’s
worth anything to them for historical value.
Regards,
Brian.
Megan,
Have you considered doing a specific gravity test on the bowl to at
least rule out some metals which you may have thought the metal to
be?
Roger
Megan,
Anyone have any idea if this actually characteristic of PT and what
those stamps might mean?
Keep in mind that a significant industrial use for platinum is, and
has been for some time, as chemical/industrial lab ware, where it’s
used in various alloys for it’s chemical inertness and resistance to
high temperatures. The guy’s father might have worked for the
Manhattan project, or not. If he worked in a chem lab of any sort
(and the Manhattan project certainly had a lot of that), he might
well have been using platinum lab ware for some types of work.
Nothing terribly unique about that, actually. Just what the alloy
is, I wouldn’t know. There are several used, including pure platinum
and others. As with most industrial items, the alloys used would be
used to match the needs of the item, not jewelery stamping laws of
conventions. Still, as with jewelry, most of these are at least 900
platinum. Check out the platinum labware part of the Kitco web site.
They might actually be a good place to consider for selling the thing
for refining. Or perhaps it is capable of being refurbished, and then
sold as labware again, which might bring more money (though I don’t
know). Again, I’d suggest Kitco as a place to start for that, since
they offer refurbishing services for platinum lab ware.
Peter
Anyone have any idea if this actually characteristic of PT and what
those stamps might mean?
Megan, platinum crucibles are pretty common in labs that need them -
read “can afford them and do that business” You can buy them at any
chemical supply house, to this day. It’s completely plausible that
that’s what you have. I don’t know the marks, but I’d guess they are
the maker’s mark (American Platinum Works? guess…) and either the
model number or maybe some rated capacity. They are .999 platinum
that I’ve ever heard of — It doesn’t need/have to be stamped
platinum because it’s not jewelry…
I recently had a customer come in to sell their scrap metal and
sold off a small hand-forged bowl with a spout. They said that it
was platinum
Certainly plausible. Platinum has many uses in industry. Bausch &
Lomb used platinum crucibles to prepare some optical glasses. A
friend of mine there was a platinum fabrication (welding) specialist.
Al Balmer
Sun City, AZ
Vince, Thank you for replying. How do you go about doing a specific
gravity test? Would it only rule out other metals, or also, allow
you to figure how much of it is alloy?
Thanks,
Megan
Are they typically hand-forged?
Are they typically hand-forged?
No. These are commercially made, not hand made. Among other things,
they’re made to rather tight specs regarding thickness, weight, etc.
Usually spun, stamped, or otherwise die formed depending on the shape
and item, and usually pretty light weight sheet metal (at the cost of
platinum, no sense making it thicker than needed, after all). I
noticed that the Kitco site, in offering platinum crucibles, also
suggests you buy, at the same time, a reshaping die made of
fiberboard(?) or something. As we all know, Platinum is soft and a
thin walled pure platinum vessel would be easily dented. So you can
get your crucible with a matched forming tool to reshape it and take
the dents out. Cool idea. Kitco also has a service where they’ll
refurbish your used crucibles when the reshaping die no longer is
good enough, such as when you’ve got little holes or tears in it…
No doubt that means they’ve got a laser welder…
Peter
Dear Megan,
You may want to insure your bowl and send it off to Gary Smith of
the Penn. Gem Lab. He has a gemological tool that shoots a laser at
any metal, vaporizes a minute amount, and can tell to the 0.0001 of a
percent what the metal content is.
This can be quite valuable when dealing with those 1920’s
"whatsaplatinum" mystery mixes. Platinum cobalt sure doesn’t work
like Platinum Iridium!
Warm Regards from the Laboratory,
Kennon Young, GG, CBJT
Member, National Association of Jewelry Appraisers
AM Candidate
USPAP Current