? About The Weight Of A 1983 Cent

You might also try going to a jewelry store to have it weighed. Also contact Ken Potter or someone like that and see if you could send it to them to look at. It may cost you a few dollars to have it done but it is a lot less then sending it to a TPG that would cost around $50.
Good luck researching this one, I hope it turns out to be copper even though it's a long shot.
John1

Didn't your scale come with a calibrating weight ?

The weights looked accurate for the two control coins (zinc and copper) when it was re-weighed so the weight of the coin in question should be accurate as well.

If not a copper planchet, I'm guessing that this being the first full year for the copper-plated zincs you might have a rolled thick zinc core planchet or possibly a heavily plated planchet. The mint was still trying to get everything right in the early years of the copper-plated zinc cents.

Instead of sending it off you can see if someone locally can do an XRF analysis (X-ray fluorescence analysis) on it. This is a non-destructive way to tell what the metal composition is of a coin.
Here is link for those not familiar with XRF analysis
https://en.wikipedia.org/wiki/X-ray_fluorescence

Places that may have a tester include jewelry stores, pawnshops, scrap metal yards or maybe even a research facility.

Best of luck and hope you have a winner.