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[Alert] Attempted sale of non-precious metal jewelry


#1

This thread has been circulating around the bay area jewelry network

  • we thought everyone would find it useful to know:

Part one:

The following was sent to me from Michael Krasow of Pacific Loan in
San Francisco :

"Rick Please forward this on to the community. A
fellow came into the store and showed me some wedding bands,
white and yellow that were stamped 14kt or 18kt even 10kt they
were in new condition with bar code labels. These are not the
normal plated brass rings that are easy to test. I tested all of
the rings, with the GXL 24 Pro plus the normal acid procedure,
cut into the edge a easy cm they tested gold, when I made
aanother cut at least twice as deep is when they tested not
gold, one white gold band even had two natural 1-2pt diamonds.

Especially in these times with the price of gold being so high
you need to take extra care in checking the gold, if they can
make these wedding bands out of this metal they can make any
piece of jewelry.

Part two:

Hello Rick,

Please post this warning in addition to the ones below.

African American male, Drivers’ licensereads Todd Hayes ,sold"
18k white gold" dog tag pendant. Staff cut and acid tested
pendant,no negative reaction to test, so item was purchased on
Wednesday 6/9/2010. Today,per the owners request,(I am the
goldsmith here) pendant was cut deep, acid tested, then drilled
over half way through and acid tested again, no negative
reaction. Then torch was taken to the item. It won’t melt.

I spoke withour refiner and he told me this is happeningquite
frequently right now. The metal is a form of Stainless Steel and
will not react to the acid or to a magnet. It is in the form of
chains, earrings, rings and pendants.

And there’s been more, but you get the point. Be careful out
there!!!

Ciao
from Sunny SF,CA
Jo-Ann & John D.


#2

On fairly large “gold” objects, you can do a specific gravity (s.g.)
determination. Here’s one good source of technique:

http://www.gold-nuggets.org/specific-gravity-test.htm

Their example calculation was based on the rogue content being
quartz with s.g. 2.65 versus gold with s.g. 19.3 If the rogue content
is base metal(s) there is still a substantial difference in s.g. with
stainless steels typically in the range 7.48 - 8.00 as per

http://www.simetric.co.uk/si_metals.htm

But if the item is small, and if the rogue content is metal(s) with
high s.g. then the accuracy of the scale needed is very fine.

I would suspect the interior rogue metal is tungsten, with s.g. 19.6
which is so close to that of gold at 19.3 you don’t have a reasonable
hope of telling the difference with this s.g. test.

What a nasty way to use up the tungsten filaments of failed
incandescent bulbs!

Mark Bingham
Fourth Axis
http://fourth-axis.com