It's on Great Collections right now. 2017 is a year that is nowhere near the last time they made cents out of copper, which I believe was 2009.
But in 2009 there were cents struck in bronze as a commemoration of Lincoln's 200th birthday (and the Lincoln cent's 100th).
I did not know (until now) that the 2009 commemorative Lincoln cents were struck in bronze and were not Zincolns. There are a great many gaps (fancy word: lacunae) in my knowledge about moderns.
Regarding the coin in the OP: what about foreign coins? Does the US Mint still strike 1-centavo pieces under contract for Panama, or is that denomination a thing of the past? (Too lazy to look it up right now.)
Hmm. I assume the composition on the label is from XRF. I wonder if XRF gives inaccurate readings on bronze because the copper would block the fluorescence from the zinc... no, I don't think that makes sense. If PCGS found they were consistently getting <1% zinc readings on coins that were supposed to be 5% zinc, surely they'd do something about it.
Not all the 2009s are copper. Most of them are zinc. There were some that are 3.1g and should have a more matte finish.
This coin was reported to be significantly overweight (2.97 grams, as I recall). That creates the possibility that this cent was struck on a zinc planchet with an excessively thick layer of copper plating. I have such an example that weighs 2.9 grams. It's possible that the XRF device wasn't able to penetrate very far into the copper plating, generating a reading that is mostly copper. This coin would have benefitted from a specific gravity test or even a crude "ring" test.
That seems more plausible. That's one downside of the increasing availability of XRF - people tend to take it as gospel, even in cases where it's not necessarily reliable. Quick Googling indicates that XRF can see maybe 0.1mm into copper. Surface area of a cent would be around 6 cm^2, so 600mm^2, times 0.1mm coating thickness would make 60 mm^3 of copper, or 0.06cm^3, which would weigh... a bit over half a gram. Which is awfully close to the excess weight for this coin!
