I overcooked this one to try to get the zinc to infuse with the copper but all I got was blisters, this was a nice smooth cent with no zinc blisters when I started.
I have heard that the 1942 was made from shell casings from the war and are a little more "yellow"; maybe they had a higher content of zinc and less tin?
Not saying that there aren't brass plated cents coming from the mint. In fact, I believe there a number of them out there. But how do you PROVE its from the mint and not PMD? As @-jeffB pointed out Zinc can migrate into the copper during heating. Environmental conditions can turn copper numerous colors. Just because you see yellowish plating doesn't prove it was mint plated brass. Did you do CIELAB or other color maping to determine the L*,a*,b* of brass plated cents? Did you correlate your vision against the color map? No. You're just giving an opinion, NOT PROOF That's what I've been saying through this whole thread. We may all believe the mint made brass plated planchets (I do). But we can't prove it with destructive testing. Cut one in half and I can prove it on XRF (lab, not handheld), XRD, or SEM-EDS very easily. But I can't do an accurate non destructive test.