Mirror 1984 quarter?

This is a quarter of my mom found in some change that she was given from a friend and we done very little research but there is a quarter out there that has a mirror like look or effect to it and this one right here contrary to the photos has a great mirror effect just curious as to what it is exactly as far as terminology and if there's any errors or anything else that anyone can tell about it as far as price worth etc would love to know the history thanks.

Hello. Can you read the mint mark (to the right) P, D or S? Your pictures are too fuzzy to see either that or and possible errors.

P

I don't see anything unusual about it. Somebody may have polished it or took it from their uncirculated collection to spend.