First successful substitutes for ivory billiard balls were made with celluloid reinforced with ground cattle bone

In the 19th century, the market for ivory products increased to an alarming point. This high demand led to the search for artificial substitutes, but ivory properties were nearly impossible to replicate. The most important substitutes came from Alexander Parkes and John Wesley Hyatt, inventors of the first artificial plastics: Parkesine and celluloid.