1982 Quarter Mint Mark Error?

I don't think that's an error. Looks like someone hit it with a punch/screw driver, PMD. There is probably an area opposite that mark on the reverse that is flattened some.

Magnetic on the affected area? What does the reverse look like?

Thanks for the extra image. But it looks like someone drilled a hole in the coin. And the hole was filled with solder. No premium for this. Just a damaged coin. I was hoping for the reverse looking normal and the area in question as being magnetic. If it were, it might be a piece of die that got struck into the coin. But so in order for this to be true, the die would have to be missing something that matched the area in question. It doesn't have this and the reverse is not normal. So it is an altered coin. Here is an interesting one that was found:

That is a genuine mint error. That piece of the die split off and was struck into the coin. (the die piece would be magnetic) So coins after happened, would then be show a Cud on that area. Also with the missing area on the obverse, the reverse would also be weak. So, just helping us to think, if something is magnetic on a coin, it might be steel? But the die would need to be showing a missing chunk from the die whether obverse or reverse. File that in the back of your mind when searching coins.

to the CCF!