The beads in-question have not been elaborately "made to look old"—and certainly not by some painstaking complicated process.

Unless I am misinterpreting what I can see, I would guess these were shiny new beads—and they have been tumbled in an abrasive that removes the shine and slightly scars them. And in this process, it's not unlikely that some of the beads broke.

This is an easy process.

Be well, Jamey