1944-S LWC Thin Planchet 2.2g

XRF would tell the alloy mix, foreign coins (unless minted here for there) are usually a bit different mix and trace elements would be different.

The Mike Diamond article is really useful, but not so much for copper. With no other US copper planchets to choose from it would be obvious if a Lincoln were struck on the wrong material (and then the math in the article would work quite well). So thin rolled or foreign has always been the two choices I know of (but very much not my area of expertise).

I've seen the foreign minted list before, but through that link I was able to download it into excel and, from my standpoint, make it more useful. Sorted by country is probably most useful to someone, but I needed it by year since that is what I was going on from the 1944-S. And after year then mint mark, and then material and could a cent be on that size planchet in the first place. Wow, what a LOT of useful information in one spreadsheet and was able to very quickly determine that the only possible known foreign planchet would be a leftover 1943 El Salvador 1 Centavo which was minted in San Francisco and had a published weight of 2.5g. So it is a 95/5 Cu/ZN mix alloy as well and therefore even it were the 1:4.9 billion chance of being on a foreign planchet there is essentially no way to prove it.

Enjoyable little exercise going through the steps to learn about this end of things. Big thanks for the input and links!

Okay, I see where I missed that. I was just thinking of foreign planchet dropping into cent hole. But yes, it would seem that it would be more likely, and somewhat more time-consuming, to figure out what a cent minted on any particular foreign stock would weigh. And after reading Mike's article is seems like there is more than a little guessing and making things up rather than science and math behind what gets labeled how by the TPG folks.