XRF Analysis

[Clens92]

Given the recent increase in fake gold and silver bars and coins, and dodgy hallmarks on certain items of jewellery, has anyone considered buying an XRF analyser?  They can be handheld or computer-based, and will give you a breakdown of the metal content without the need for destructive testing.

If anyone has any experience with them, or could recommend a decent model, that would be great.

I think it's going to become increasingly necessary as gold-plating becomes thicker, and the fakes get more and more convincing, for XRF analysis on nearly every purchase.

 

[ifing]

since i sawthe post from morezone about his, i looked into it and want one too. But the price is still to high for me.  @morezone

[mr-dead]

I think for what a good one costs you might as well stick to buying from well known trusted dealers.

It would take a lot of Ebay bargains to make up the difference in price.

[ApisMellifera]

Yeah Morezone has the Sigma Metalytics Precious Metal Verifier an amazing device but pricey.

You can even confirm metal content with the coin/bar still inside the original packaging or capsules  .

Here are a few youtube video's

https://www.youtube.com/results?search_query=Sigma+Metalytics+Precious+Metal+Verifier

[morezone]

Last time I checked XRF was still very very pricy. Not sure how much they cost now but at the time the PMV was the only thing available at an affordable price point.

It is a great device and I've been meaning to make a full in depth video of it for some time.

[MickB]

A work colleague takes his purchases of scrap gold to jewellery quarter in Birmingham to be tested on one of these devices. They don't charge him as he's a regular customer, so it saves him forking out for one. I did look at the price of one but just like dvd players in the late 90's, they'll come down in price eventually.

[Clens92]

1 hour ago, ApisMellifera said:

Yeah Morezone has the Sigma Metalytics Precious Metal Verifier an amazing device but pricey.

You can even confirm metal content with the coin/bar still inside the original packaging or capsules  .

Here are a few youtube video's

https://www.youtube.com/results?search_query=Sigma+Metalytics+Precious+Metal+Verifier

 

I did look at these, but I've seen several reports that it's been fooled by simple cladding, so wouldn't trust it entirely.

 

[Paul]

For absolutely iron clad guarantee of 100% genuine products and not having to ever worry about authenticity just buy brand new 2016 core bullion products direct from Royal Mint Bullion

As they own every aspect of melting, casting, minting, production and distribution.  

If those extra few pound they charge gives you peace of mind over a lifetime it is money well spent

[Bumble]

An XRF scanner can only test the surface of a metal. X-rays, like light, cannot penetrate into the inside. So it will tell you that the surface of a bar is 999 pure gold, but not that it is just gold plated tungsten. To test the inside you need an ultrasound scanner. Sound waves pass right through a solid object and their speed depends on the material, so a solid gold bar can be distinguished from a gold plated one.

[Clens92]

23 minutes ago, Bumble said:

An XRF scanner can only test the surface of a metal. X-rays, like light, cannot penetrate into the inside. So it will tell you that the surface of a bar is 999 pure gold, but not that it is just gold plated tungsten. To test the inside you need an ultrasound scanner. Sound waves pass right through a solid object and their speed depends on the material, so a solid gold bar can be distinguished from a gold plated one.

Are you sure...? I saw a handheld XRF detect a fake Perth Mint bar today; and Hatton Garden Metals use an XRF to determine what carat jewellery they get sent.

Tungsten would be a tough issue due to its similarity to gold  - same atomic weight etc.

[Bumble]

Pretty sure this is correct. Check these links:

http://fisherpreciousmetals.com/2016/06/counterfeit-coins/
http://www.popsci.com/diy/article/2008-03/how-make-convincing-fake-gold-bars
http://www.aurotest.com/welcome.htm
http://testyourgold.com/preppers-guide-to-gold-and-silver-testing/

X-rays will penetrate to about 10-20 microns. A fake bar might be detected if its percentage of gold is less than expected; XRF will also determine the carat, but again, only in the surface. Ultrasound is the only non-destructive test that can discover gold-covered tungsten.

EDIT... Here is another link: Olympus manufacture both XRF and Ultrasound scanners and they specifically mention that XRF only scans the surface:

http://www.olympus-ims.com/en/applications/ut-testing-gold-bars/

[gazer]

On 05/07/2016 at 18:05, Paul said:

For absolutely iron clad guarantee of 100% genuine products and not having to ever worry about authenticity just buy brand new 2016 core bullion products direct from Royal Mint Bullion

As they own every aspect of melting, casting, minting, production and distribution.  

If those extra few pound they charge gives you peace of mind over a lifetime it is money well spent

VERY good advice. ?

[Murph]

Perhaps a bigger non portable machine can scan a bit deeper as it would then be possible to use more energetic x-rays and provide shielding but it would certainly cost.  

The density of any coin/bar would be problematic to reproduce, so that along with visual inspection should weed out most fakes.

[sovereignsteve]

5 hours ago, Murph said:

Perhaps a bigger non portable machine can scan a bit deeper as it would then be possible to use more energetic x-rays and provide shielding but it would certainly cost.  

The density of any coin/bar would be problematic to reproduce, so that along with visual inspection should weed out most fakes.

I don't think that would be possible.

It may be possible by increasing the intensity or lowering the wavelength of the x-ray to penetrate deeper into the subject material but I doubt the returning photons of energy would be powerful enough to return to the detector from any increased depth.