Message:

<p>[QUOTE=&quot;desertgem, post: 2425181, member: 15199&quot;]XRD is X-ray difraction , and is mainly used for crystalline structures. Historical note: DNA structure was predicted by XRD done by Rosalind Franklin for Watson and Crick. It would work to identify chemical crystals, proteins, etc. on the surface of coins, the total thickness object would have to be powdered.</p><p><br /></p><p>XRF is a statistical comparison of the signals of certain atoms as they goes through the cycle. The surface atoms will be a larger statistical value due to proximity compared to inner area, so even though power can be increased, the 3D resolution can not just isolate on a certain cubic area for analysis. My suspect would be that the patina would be over-represented chemically than the inner material by external analysis. That is why such can not be used to detect gold plated tungsten bars reliably and ultrasonic waveform analysis is used instead.[/QUOTE]</p><p><br /></p>

Your name or email address:

Do you already have an account?

• No, create an account now.
• Yes, my password is:
• Forgot your password?

Stay logged in