1920 Wheat Only 1.9 Grams!! Help

I have a British penny in uncirculated condition, that was deliberately struck on a thin planchet. All of the detail is sharply struck up.
It was struck just at a time just before The Royal Mint was re located from London to Llanstrisant, in Wales.

A few coins with deliberate errors were illegally struck by the employees, in protest against the re location.
I guess that a lot of the employees would have been retrenched, and at least some of them would have strongly disliked being retrenched.
The error coins were just thrown over the perimeter wall, to be picked up by passers by.

Dimes are smaller in diameter, but it cannot have been struck on a dime planchet, because a Wheat cent is shown. Silver dimes at that time of wheat cents weighed 2.5 grammes.
It is VERY underweight for a Wheat cent, AND for a silver dime as well.

The image is not enough detailed to see the date, but the colour suggests a zinc coated steel cent, dated 1943, which weighed more than a silver dime, anyway.
It such a coin had been acid treated, it would have been black in appearance. Acid could have very easily eaten the zinc coating away, because it would have been preferentially attacked. Buffing the coin after acid treatment would seem plausible in this case.

Such musings lead me to believe that 'toner' is correct.

The U.S. Mint in 1943 was executing coinage orders for a number of foreign Countries. There is a possibility that a blank for one of those Countries could have been used. However, much better pictures are needed to check for this possibility.

Hmmm so someone dipped it in acid then tried to clean it up or tried to tone it to a different color? I thought acid ate away the rim first but it has a full rim and a shiny copper color around the rim. Someone probably tried to change it and sell it but just ruined it!!

Your coin is smaller in diameter. Back in the 1960's they used to take a cent to science class, dip it in acid and reduce the size to a dime. Then they would take it to a soda machine and get a soda for 7-10 cents. If they got a 7oz. bottle they had change for the next three bottles. (I never did this though.)

Lol someone always finds a way to cheat the system. I guess that's very creative though and a good story!
That's a dramatic difference in the coin tubes...very good example! I'll still hold on to it just because it's different. My uncle thought it was really neat but then again he knows nothing about coins

They were 6.5oz bottles of Coca-Cola then Coop.

Somewhere around here, I think I still have an empty 12oz glass Mountain Dew bottle. "It'll tickle your innards!"

I wish I was a kid in that time! What am I gonna have to collect, the famous 20 oz plastic bottle lol my 1941 must be acid though because it only weighs 2.7