Breaking news - unhealthy Platinum levels found in chocolate coins

[Silverlocks]

Apropos of this video below, I'm minded to write a few musings on X-ray fluorescence as my cousin's milkman actually used to drive one for geochemical analysis back in the late Jurassic.  This was the 1980s when just the X-ray tube for an XRF machine was as expensive as a whole machine is now, and while one could get a grant to buy the thing, it was next to impossible to get a grant to buy the tubes needed to run it - which used to pop expensively every two and a bit.

So, it seems @LawrenceChard found unusually high levels of Platinum in some chocolate coins.  As I know a (very) little about XRF machines and a bit more about computers I'll offer my two bob worth about how that happened.

So, with a minor nerd warning -

Normal fluorescence - high vis vests, for example - is when UV (or even visible wavelengths) interact with electrons in their orbitals, causing them to pop up and down, releasing light of a particular wavelength in the process.  As this happens in the electron shells, the energies of the shells (which determine the wavelength of the light emitted) vary with the individual type of atoms.  The molecular structure the atoms are bound in also affects these energies, which is why certain compounds flouresce differently than others.

X Ray fluorescence uses light at much higher frequencies (X rays) to cause fluorescence in the particles within the nucleus itself - the protons and neutrons.   Depending on the structure of the nucleus, these fluoresce at different wavelengths, giving each atom (isotope in fact) a distinctly different spectrum.  These are also unaffected by molecular bonds in the way that fluorescence from the electron shells is.

You can see multiple peaks for each atom here.

Now, the analysis software in the XRF machine analyses the peaks and matches it to a database of patterns expected from different metals, probably using some sort of fuzzy matching algorithm (more on this later).  A lot of other things (text searches, for example) use fuzzy matching of one sort or another to get a closest match; I won't go into the details but it makes for good reading if you're having trouble getting to sleep.

I think (and this is purely speculation) that the XRF machine thought the chocolate had platinum in it as some combination of other elements produced peaks where the machine was expecting to see the peaks produced by Platinum - at least within the tolerances of the matching algorithm.  This has led the machine to produce a false positive for platinum.

Why does it matter?  Because it suggests that it might be possible to formulate something capable of spoofing a particular XRF machine if you knew enough about the software to find vulnerabilities, although this is likely pretty far fetched.  It's also going to be a bit harder to find something capable of spoofing that, and one of the induction testing devices and a specific gravity test, though.

But it's an interesting thought, and it does suggest that @LawrenceChard et. al. might want to bring the issue up with the manufacturer as it looks like their software might be a bit c**p.  I would suggest trying the chocolate coin out on some different machines if you can get hold of them, just to see what they come up with.

 

 

Edited August 28, 2022 by Silverlocks
Fat fingered typing.

[LawrenceChard]

On 28/08/2022 at 16:46, Silverlocks said:

Apropos of this video below, I'm minded to write a few musings on X-ray flourescence as my cousin's milkman actually used to drive one for geochemical analysis back in the late Jurassic.  This was the 1980s when just the X-ray tube for an XRF machine was as expensive as a whole machine is now, and while one could get a grant to buy the thing, it was next to impossible to get a grant to buy the tubes needed to run it - which used to pop expensively every two and a bit.

So, it seems @LawrenceChard found unusually high levels of Platinum in some chocolate coins.  As I know a (very) little about XRF machines and a bit more about computers I'll offer my two bob worth about how that happened.

So, with a minor nerd warning -

Normal flourescence - high vis vests, for example - is when UV (or even visible wavelengths) interact with electrons in their orbitals, causing them to pop up and down, releasing light of a particular wavelength in the process.  As this happens in the electron shells, the energies of the shells (which determine the wavelength of the light emitted) vary with the individual type of atoms.  The molecular structure the atoms are bound in also affects these energies, which is why certain compounds flouresce differently than others.

X Ray flourescence uses light at much higher frequencies (X rays) to cause flourescence in the particles within the nucleus itself - the protons and neutrons.   Depending on the structure of the nucleus, these flouresce at different wavelengths, giving each atom (isotope in fact) a distinctly different spectrum.  These are also unaffected by molecular bonds in the way that flourescence from the electron shells is.

You can see multiple peaks for each atom here.

Now, the analysis software in the XRF machine analyses the peaks and matches it to a database of patterns expected from different metals, probably using some sort of fuzzy matching algorithm (more on this later).  A lot of other things (text searches, for example) use fuzzy matching of one sort or another to get a closest match; I won't go into the details but it makes for good reading if you're having trouble getting to sleep.

I think (and this is purely speculation) that the XRF machine thought the chocolate had platinum in it as some combination of other elements produced peaks where the machine was expecting to see the peaks produced by Platinum - at least within the tolerances of the matching algorithm.  This has led the machine to produce a false positive for platinum.

Why does it matter?  Because it suggests that it might be possible to formulate something capable of spoofing a particular XRF machine if you knew enough about the software to find vulnerabilities, although this is likely pretty far fetched.  It's also going to be a bit harder to find something capable of spoofing that, and one of the induction testing devices and a specific gravity test, though.

But it's an interesting thought, and it does suggest that @LawrenceChard et. al. might want to bring the issue up with the manufacturer as it looks like their software might be a bit c**p.  I would suggest trying the chocolate coin out on some different machines if you can get hold of them, just to see what they come up with.

 

 

You have to be careful when using flourescence instead of fluorescence.

Unless you are using flour essence, wholemeal or otherwise.

Using the wrong product will make your bread glow in the dark, and you end up with light sticks instead of bread sticks.

If you try to measure flour essence using an XRF machines, when you see the results, you might go "Doh", or "Doe"

😎

Edited September 1, 2022 by LawrenceChard

[Silverlocks]

Oh dear, I may have fat fingered the keyboard.

On the other hand, software being a bit c**p doesn't really come as a surprise.  Just imagine the quality control standards on the software going into your internet connected smart fridge or doorbell.

Edited August 28, 2022 by Silverlocks

[LawrenceChard]

Just now, Silverlocks said:

Oh dear, I may have fat fingered the keyboard.

Don't worry about it, just have some chocolate instead.

I recommend 70% cocoa solids at minimum.

Aztec Gold also shows up pretty well on XRF machines!

😎

[Silverlocks]

I wonder if @BackyardBullion knows enough folks with XRF machines to make a video about trying out the chocolate coin test on them?

[Gordy]

you lost me at Apropos... from then on in it was all downhill for me... so I opened another beer and some chocolate.... 

[Silverlocks]

2 minutes ago, Gordy said:

you lost me at Apropos... from then on in it was all downhill for me... so I opened another beer and some chocolate.... 

Well, mine was glowing after I put it in the XRF machine, so I kind of went off it . . .

[SidS]

20 hours ago, Silverlocks said:

Oh dear, I may have fat fingered the keyboard.

Sorry, but that comment just reminds me of this Simpsons classic...

 

[Silverlocks]

Well, I'm fortunate that nobody would ever confuse me with Homer Simpson, as nobody in their right mind would let me run a nuclear power plant.