Were early pool balls made from ivory?

Dear Matthew:

The recent acquisition by my next-door neighbor of a pool table has set me to pondering. According to M.S. Encarta, early billiard and pool balls were made of ivory. I'm surprised. Is ivory that tough? Surely these early balls tended to crack and splinter. In any case, that's the minor question. The main part is, how did they get them to be perfectly, flawlessly round?

-- Behind the Eight in Clairemont

Of course, they didn't. They weren't even the same size most of the time. From the 1500s to the late 1800s, a billiard ball maker turned the roughed-out ivory on a lathe with one hand and held the carving blade in the other. Ivory's fairly tough, but it's porous, so the balls eventually shrank and cracked. To solve that problem, the best ivory balls were gradually seasoned as they were carved, a two-year process from beginning to end. If you chipped one, you'd return it to the carver and he'd smooth it out. Old-timey billiards was probably a little like poking eggs with a stick. The game was a 15th-century form of indoor croquet, once played with wooden balls, macelike mallets, and a table-top wicket (no pockets). The green felt was originally meant to imitate a grassy lawn.