Thanks, everyone, for your responses. It appears XRF is a valid tool for measuring ImAg thickness.
I still have a need to have a few PCB samples analyzed. I have some PCBs that show ImAg copper-like discoloration after only 1 reflow cycle on the non-populated side. I would like to confirm what this discoloration is, and investigate / confirm if it is due to ImAg plating thickness or porosity issues.
Offline responses ok.
Thank you.