It is
Machine Doubling. (
which is a poor term for it as nothing is doubled)
Machine Doubling reduces the size of the devices. Enlarging the image more shows that after the strike happened, the the dies damaged the devices after the strike Sometimes with a hop/slide/twist or bounce. I usually call it machine
damage rather than machine
doubling because,
nothing is actually doubled. Instead a doubled die shows a raised area and not an incuse area on the devices:

Edited by coop
05/31/2019 2:07 pm