1982 Lincoln Cent wrong alloy

i have a Lincoln Cent 1982. It is silver and made out of 1% iridium, 64% zinc, 34% copper and the rest Nickel. Is anyone familiar with this coin?

 

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pictures, weight...

 

Nope.. I doubt that
How did you get those results?

 

I am trying to load them. 2.6 grams.

 

2.6 grams would be just a normal Copper Plated Zinc Cent.

 

Let's see a photo or two of the coin.

The weight of it, as noted above by PM98, is normal.

Without seeing photos, there's a chance
that the 1% iridium came from the parking lot.

 

I got the same reading on three machines.

 

Could be a weird reading from the staples on the 2x2

 

What does the machine read for a handful of other post-1982 cents?

I'm not surprised that it would read high on copper, with a thin but dense copper shell over a zinc core. I wonder if the nickel and iridium components are because it's trying to make sense of a non-uniform composition, with the zinc spectrum attenuated as it passes through the copper. (I have no idea what the spectra for these four metals look like, so that's just a wild guess...)

 

Almost impossible those are correct, as I don't think the zinc is alloyed at all.

 

wheres Mulder and Scully when you need them?

 

The coin was not in the 2x2

 

If that is the actual color of the coin, it looks like it has been plated.

 

It's a 2.6 zinc planchet that has been
plated over. If the copper plating was removed,
the surfaces would look different.

It's been plated, imo.

 

You are right on the parking lot .
Coin has environmental damage ...

 

I believe that @-jeffB generally has the right idea. I would expect a post mint zinc plated cent to have a copper/zinc composition like you see. The Xrays do penetrate slightly below the surface of the sample (depends on the material but it is deeper than normal plating thicknesses). So your results show the zinc the post mint plating and is also picking up the copper plating layer in the original planchet below it (and some of the Zn may also the original zinc blank, but can't say for sure and isn't that important to this discussion)

I wouldn't get hung up on the trace elements like Nickel and Iridium. They could be junk in the plating bath or electrodes, but IMO, they are just errors in the algorithm used by the machine to calculate the results.

If you look at your picture of the readout screen in post #8, notice the graph above the composition readout. Based on the energies and heights of the peaks, the machine calculates the specific elements and amounts. It has Sn (tin), I (iodine), and Ag (silver) over some of the small peaks but these don't show up in the compositional analysis. Trace level elements can be hard to accurately tease out of the noise and I'm sure the manufacturers of the handheld units are more concerned with their equipment detecting precious metals correctly than determining exotic trace elements.

Maybe the mint got ahold of some of the meteorite that caused the dinosaur extinction at the Cretaceous-Tertiary boundary event (it was high in iridium) to make some experimental planchets, but more than likely, you just have a normal cent that was zinc plated after it left the mint

 

Iridium -nickel compounds are used for plating things such as jewelry , spark plug tips, etc., and the cent does have the surface appearance and weight of a plated cent with some wear.
Jim

 

I stumbled over that I, too. I assumed it was supposed to be Ir, but was clipped off the edge of the display.