Investigating the drilling of ancient beads provides a reasonable interpretation of how the perforation was accomplished. In other words, what the drill or drill-bit was, and whether it was slow-turned (as with a bow), or mechanically drilled (as with an engine). Some hard stone beads have been pecked—and this also creates a distinctive perforation.)

One cannot actually date a bead by it's perforation. But knowing how the perforation was formed provides evidence that may suggest a likely time range, via the techniques and mechanisms used, and the knowledge of who had and exploited this technology.

And, by the way, the shaping of a (stone) bead, its polishing, the art-sense of the beadmaker (in terms of how variegated stones were exploited for particular sorts of patterns), and its condition, all contribute to recognizing a bead as probably ancient or probably not ancient.