Synthetic-tooth Pool Balls

The balls used for billiards, snooker, and pool used to be made from ivory.

With a dwindling supply of elephants, manufacturers turned to plastic as a replacement.

Plastic is superior to ivory in many ways: it isn't as fragile, it doesn't require humidity and temperature control (ivory balls were notorious for cracking if they got too dry), it's less expensive, and it doesn't contribute to the extinction of a species.

But plastic suffers from being too slick.

If you drag a natural pearl gently over the face of one of your front teeth, you will feel a grittiness. That's caused by the surface of the pearl being rough (at microscopic dimensions), and the roughness matching the roughness of your tooth. Similarly, if you drag a piece of ivory over your tooth, it feels rough.

If you drag a plastic pearl over the same spot, it just slides. There is no grip.

Billiards, snooker, and pool require fine cuts--shots where the cue ball and the object ball barely touch. When the balls are slick, there is a limit to how fine a cut can be before the contact patch slips instead of gripping. When the contact patchs slips, spin is not transferred correctly from the cue ball to the object ball, and the shot suffers through no fault of the player.

What we need is balls with a surface that is microscopically rough, like ivory. This surface should not wear off, or wear down. Perhaps it could be implemented by embedding fine particles of something hard and gritty in the plastic.

This seems like the kind of thing 3M could knock out in an afternoon.