2008-D LMC Improper Annealing?

@silviosi, I do not appreciate the derogatory statements toward Californian nor my level of intellect. If I do not understand something, then isn't that the perfect opportunity to dive in and learn? The whole point in me joining this community is to LEARN. The difficult part I'm having is the language barrier we have. No to offend you, but I have to read your statements over and over to make sure I'm understanding you.

I'm still unsure if you think this was caused pre or post minting.

I'm not trying to prove that I am right. I am just a curious soul. It was suggested that applied heat caused this issue post minting. If that is the case. How might one suggest it was done? I tried a few different ways from the aforementioned above.

I can try copper plating a coin to see for myself how it concentrates in the center first. But aren't the metal sheets plated before the blanks are punched? So plating a coin wouldn't be the same. If I do try plating a coin. How would you recommend I suspend the coin in the copper sulfate solution without the hardware effecting the plating? Alligator clips would leave uneven copper plating where it's secured to the coin. Could I set the coin on the bottom of the glass beaker? Would the side on the glass get coated? I will look into this later.

Thank you for the suggestion on the coin show. Maybe I can get the time to make it there.

This are some of the ones I found in string rolls.

@ Cu : the color is a normal Zn who come back to his normal stage.
@ PETE: Normal the blanks is suppose to be clean after blanking?!!!? I like your hypotheses.

Me I supposes some could be from the Heats of the Dies. In time I present to the Mint the Document about over heat of the Dies and the danger for the production quality, but as the Mint is do not come back to you.

@Numismax: Far from me to offend you, but to go more far will be complicate. I speak scientific dialect and not the common language, I teaches in DC Mc Hill, in Corpus Christy in Montreal McGill but science. I had residents from over the word and no problems till here sometimes some persons do not accept my way to show what is my opinion and them to analyze what it is..

Is very good to be curious and try to learn and here it is the place for the coins not the forensic of the coins.


PS: The electroplating of the blanks do not use copper sulphate

Excellent DATA. You nail all the suppositions here. PM me to has an interesting Doc for an DATA Dragon.