Grease filled die. Were it a copper coin rather than a copper plated zinc coin, I would have also thrown out deliberate wear of the coin.
Time for more coffee.
Edit:
I should add that obscured image through excess die lubricants, commonly referred to as grease filled dies, regardless of type of lubricant, is fairly common in all coins.
There is collector interest, but that is limited and somewhat specific from one collector to another.
Premiums in most cases are very low.
Still time for more coffee.