Billiard Ball - Wikipedia

Early balls were made of various materials, including wood and clay (the latter remaining in use well into the 20th century). Although affordable ox-bone balls were in common use in Europe, elephant ivory was favored since at least 1627 until the early 20th century;[1]: 17  the earliest known written reference to ivory billiard balls is in the 1588 inventory of Thomas Howard, 4th Duke of Norfolk.[2] Dyed and numbered balls appeared around the early 1770s.[1]: 17  By the mid-19th century, elephants were being slaughtered for their ivory at an alarming rate, just to keep up with the demand for high-end billiard balls – no more than eight balls could be made from a single elephant's tusks.[citation needed] The billiard industry realized that the supply of elephants (their primary source of ivory) was endangered, as well as dangerous to obtain (the latter an issue of notable public concern at the turn of the 19th century).[1]: 17  Inventors were challenged to come up with an alternative material that could be manufactured, with a US$10,000 (worth approximately $241,875 in 2025[3]) prize being offered by a New York supplier.[1]: 17 

Although not the first artificial substance to be used for the balls (e.g. Sorel cement, invented in 1867, was marketed as an artificial ivory), John Wesley Hyatt patented an "ivory imitation" composite made of nitrocellulose, camphor, and ground cattle bone on May 4, 1869 (US patent 89582, the first US billiard ball patent). The material was a success, and was sold as Bonzoline, Crystalate, Ivorylene until the 1960s, and was used by prominent professional players such as John Roberts Jr (1847–1919), Charles Dawson (1866–1921), and Walter Lindrum (1898–1960). The ivory substitute was one of the most significant early reinforced plastics; induced the global growth of billiards, pool, and snooker; and helped create a modern idea that the artificial can surpass the natural.[4][5] It is unclear if the cash prize was ever awarded, and there is no evidence suggesting he did in fact win it.[1]: 17 [6]

However, Hyatt's composite had problems. One of the most relevant is cellulose nitrate flammability, not because of making the billiard balls explode, as is often claimed, but because of the dangers of handling it in its pure form during manufacturing. Another problem was related to camphor mass exploitation, leading to the devastation of Taiwan's forests and displacement of indigenous communities.[4][7] Subsequently, the industry experimented with various other synthetic materials for billiard balls such as Bakelite, acrylic, 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 name Aramith and other private labels, manufactures phenolic resin balls.[8][9] Other plastics and resins such as polyester (similar to those used for bowling balls) and clear acrylic are also used.

Ivory balls remained in use in artistic billiards competition until the late 20th century.[1]: 17