As mentioned these are die scratches to remove previous clash marks. Not a premium for these. All dies can have them. The ones in the outer field ares go away fast. The ones around devices last longer. In side of a contained area like inside of the device/mintmark will last longest. They come and go away fast, but are like fingerprints for a variety die. But nothing special to collect. Just a step up on the ladder of knowledge. Keep climbing.