What are billiard balls made of?

Question

I think it's a type of ceramic, but I'm not sure.

Answer 1

Hardened Plastic.  Cellulose Nitrate to be sure.

Answer 2

In 1869, John Wesley Hyatt invented a composition material called cellulose nitrate for billiard balls (US patent 50359, the first American patent for billiard balls). It is unclear if the cash prize was ever awarded to Hyatt, and there is no evidence suggesting he did in fact win it. By 1870 it was commercially branded Celluloid, the first industrial plastic. Unfortunately, the nature of celluloid made it volatile in production, occasionally exploding, which ultimately made this early plastic impractical.

Subsequently, to avoid the problem of celluloid instability, the industry experimented with various other synthetic materials for billiards balls such as Bakelite, Crystalate and other plastic compounds.

The exacting requirements of the billiard ball are met today with balls cast from plastic materials that are strongly resistant to cracking and chipping. Currently Saluc, under the brand names Aramith and Brunswick Centennial, manufactures phenolic resin balls. Other plastics and resins such as polyester (under various trade names) and clear acrylic are also used, by competing companies such as Elephant Balls Ltd., Frenzy Sports, and Vigma.

Answer 3

I believe the inner core is a type of wood or wood like substance, maybe cork and they are coated with a plastic but with a glaze to prevent breakages and to make that signiture click sound