Sorry, but they not errors. It's environmental damage. They may be metal detector finds, or have been sitting outside for awhile. If you look at the one on the right, noticed all of this nicks and dings. That's a good indication that it may have been spent time sitting in a parking lot or road
After I went through my girlfriends change and found a few winners, her son asked me if I would go through a mug full he had just cleaned out of his truck. He's a slob really but nearly every coin except for the cents looked like this. The cents were so bad I wouldn't even touch them. Seems it had been about three years since he did a major cleanup of the floor. Yep, environmental damage to all of them.
LOL. @tommyc03, someone posted the other day about an initial coin supply order to get started in the hobby. From your recent experience maybe we should all add a pair of disposable latex gloves to the list. Steve