1983 Lincoln cent missing clad acid wash or what

Guys, please review attached pics of 1983 Lincoln cent and as the title asks what happened here? Is it a mint error or another high school science experiment gone wrong and hence, pmd? Thanks in advance for taking a look and feedback!

 

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Looks like Environmental Damage. And xould also be the copper plating was stripped off. Yes.. it is known how to do it.

By the way Cents are Plated with Copper.
Dimes, Quarters and Half Dollars have a Clad layer. They are 2 different processes done 2 different ways. I will try to find the definition of the difference.

 

In a 'clad' item, it has had a skin of another material mechanically bonded onto it whereas a 'plated' item has had the skin electrochemically deposited.

 

clad - sheets of cold metal are bonded together in a sandwich - All our modern dimes, quarters, and half dollars are clad. They have a copper core and layers of copper-nickel on both sides.

plating - metal objects dunked into another metal in liquid form. The liquid metal coats the other metal and dries when pulled out of the 'bath'. Zinc cents are plated with 100% pure copper.

 

I'm assuming the copper plating process is similar if not identical to chrome plating. I'm not familiar with the de-plating process but do you know if that process leaves those metal bubbly streaks running in straight lines randomly on both the oversee and reverse of the cent? This definitely falls into the pmd column.

One follow-up question if you don't mind, kind sir, does pulling the copper plate off the coin considered the same as melting Copper coin down for it's Copper and also illegal or since they haven't melted the coin but rather removed just the plating so that law against melting cents not applicable?

 

I think the copper is still there, it just has discoloration due to environmental damage. You wouldn't see the raised plating bubbles if the copper was gone

 

The copper plating has been
removed.

 

take a closer look at the pictures with the rim showing--the entire rim of the coin look like a steel ring around the coin. I also forgot to state that the coin weighed out at 2.46g. that should help determine if the copper plating has been removed or not.

 

Rinse and repeat -

 

And the bonding is done by high pressure rolling of the sheets.

Plating is done by immersing the metal object in and electrolyte solution that has metal ions of the metal you want to plate onto the object. Another piece of that metal is also placed in the solution. The an electric current is run through the solution withthe object to be plated connected to the negative terminal and the other piece of metal to the Positive terminal. Positive metal ions in the solution will plate onto the object, and atoms will come off the other piece of metal to replace the ones lost from the solution. Eventually a layer of metal will be built up in the object.

What paddyman describes as plating would more correctly be termed as coating.

 

One more thing the coin feels somewhat rough to the touch as if the copper plating was removed. If anyone knows the answer to my last question about legality of removing the copper top layer, I'm simply curious. Thanks again for everyone's feedback regarding this very strange coin-never seen anything like it!

 

Looks to be a plating blister on the front. So the plating was not removed.

 

Paddyman, thanks for looking at this coin in greater detail! So it weighs out at nearly 2.5gm, which would also lend further credence to the plating not being removed, correct? So what's going on with this coin, can it possibly be mint damage? Or am i back to my original question about this coin?

 

PMD.

 

The copper plating has been removed.

The weight of the copper plating is almost
nil, in comparison to the weight of the
zinc planchet, so it's not indicative of
anything else.

 

Ok, i was willing to go with that answer the first go-around of feedback; thanks guys! Since the amount of copper plating is negligible, I'm guessing this isn't the start of some criminal scheme to remove all copper plating from the zinc core cents. PMD and someone testing their skills in removing plating. Sounds good to me, thanks again gents for solving this mystery coin's disposition.

 

The mint reported that the copper plating is 8 microns thick. My quick, “back of a napkin” math says that the copper coating should weigh around 0.18 grams (assuming surface area is a simple disk 19.05mm in dia x 1.52mm thick) or leave a coin weighing 2.32 gms. (hopefully, I did the math right)

If you have a scale with the correct precision and it’s calibrated, you should be able to measure the difference. However, I don’t know the standard tolerance for these, so the copper weight change may get lost within the weights of a normal cent.

 

Tolerance is .13 of a gram.

With tolerance, and scales not
being exact in many cases, I
don't believe that weighing such
a coin would be helpful as to an
authentication point.

These are easily identified from the
surfaces and color of the cent.

The general rule:

Dark/dull and greyish - the plating has been removed

Bright and Shiny - it's been re-plated as a novelty item.

 

Cent weighs 2.5 grams and the overall composition is supposed to be 97.5% zinc and 2.5% copper. That is by weight. So 2.5% of 2.5 grams is .0625 grams of copper.

 

I like your use of gloves to handle the coin, so as not to leave fingerprints!