Do NGC or PCGS ever use XRF machines for coin authentication?

I’m guessing he means the best consumer grade XRF machines.

Like one of the Olympus ones. They cost about $13,000 which most people couldn’t afford but PCGS & NGC most definitely could. Especially if it means it helps them avoid fakes considering they guarantee authenticity.

There are a lot of coins worth over $13,000 and if a fake one got by and got slabbed they would be responsible for reimbursing the person who bought it for the fair market value of the coin and it would be a disaster if it was an expensive coin like that.

I’m also guessing (I can’t say for sure though) that they spend more time & resources on the expensive stuff specifically to prevent such situations.

For example they probably don’t spend much time on say a PF67 1955 Roosevelt Dime since if they mess up it’s only like $30 to reimburse but if it’s something like an AU58 1893 S Morgan Dollar and they screw up it would be a catastrophic disaster for them since they’d be on the hook for ~$95,000 owed to the customer for their mistake.

 

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every organiation which is invovled in conservation has industrial level tools on this technology, not to mention a catscan and other tech. In the house it might be expensive, but on a business scale, is is an essential tool. What do they use to inspect plane parts?

 

https://bergmann.physics.wisc.edu/wp-content/uploads/2021/02/pub189.pdf

 

No, it's about Laser-Stimulated Fluorescence being used on fossils, as it says in the abstract. It mentions some elemental analysis they did on one of the SLAC beamlines, but only in passing -- that's not the point of the paper.

 

Thanks for your links and your opinions.

 

It's worth emphasizing that @calcol's opinions on this topic appear to be very well-informed.

 

this is the work done by SLAC, in a lecture that explains the technology

 

just more on the technology being used in the arts
https://www.metmuseum.org/perspectives/articles/2021/9/david-lavoisier-conservation

https://events.cornell.edu/event/classe_seminar_louisa_smieska_metropolitan_museum_of_art

 

No offense, but I thought we were talking about a hand-held XRF gun that costs about $1500.00 to $2000.00, not ".. a billion-dollar facility."
From everything I've seen(a gun in use), read(the readout as it's being used and the factory user's manual), and talked to actual XRF gun users(and manufacturer's representatives) about, I believe the gun can penetrate a coin, if not through the coin, then at least far enough to do a spectral analysis.

Bottom line : I trust it to accurately test my coins.

 

https://www.olympus-ims.com/en/xrf-xrd/xrf-handheld/

 

Oh I actually saw something on TV pretty cool about authenticating old art works.

Apparently one method they use is testing the wood & paint for uranium molecules. After the first nuclear weapons tests in the 1940s there were tiny amounts of uranium all over the world so if the wood from the frame or in the paint has uranium in it they can prove without a doubt that it was made after 1945.

Good luck trying to fake a Da Vinci or an Old Master painting.

 

No offense, but did I say his opinions weren't well-informed?

 

Thanks for your links and opinions.

 

Okay, yeah, I'll admit the APS was over the top. When someone says "the best of the best", I let my imagination run free.

As for hand-held gun cost, if somebody one day produces a reliable hand-held XRF the price of a double eagle, I'll be first in line to grab one. Today, they start around ten times that. I've seen used ones offered for less than $10K, but with no guarantees.

The numbers I've found indicate that effective penetration depth in gold is much less than a millimeter. Remember, the higher-energy X-rays have to get into the deeper sample, but then the lower-energy fluorescence X-rays need to get back out, too. If there's just thin gold plating, the gun will see through it. If there's a half-millimeter or more of gold around a tungsten core, it can't. To detect that, you need a sonic or electronic method.

 

your sun glasses is killing us!

 

more than enough for gold foil detection and you can do the back and the front... no extra charge

 

I know that no technology can identify all fakes. But shouldn’t we use the technology available to do the best we can?

Just like a scale can weigh a coin it may not identify all fakes but if a fake does happen to be the wrong weight at least it identifies that one fake which might not have been identified without the scale.

 

AI will be able to ID them better than humans. Give it a year or two tops.

 

Not a year or two, but eventually, I agree.