Professional billiards balls are extremely durable. In fact, hopping one off the table onto a concrete floor will inflict no damage. This is great because the smallest dent could affect the playability of the ball—how it rolls and ricochets.
Nevertheless, balls sometimes need replacing after considerable use. This is more common among sets made from polyester and acrylic. Aramith balls, manufactured from phenolic resin, are said to last five times longer than other balls.
Interestingly, cheaper balls threaten the longevity of the billiards cloth. Balls resistant to scratches are smoother, causing less friction and wear along the path it rolls. This is another advantage Aramith balls provide—stronger surfaces.
Replacing a Single Ball
If you lose or damage a billiards ball, it is paramount that you replace it with one of the exact same balance, density and composition. Inconsistencies in said areas cause erratic ball behaviour like wayward rolling and inconsistent banking. That said, replacing a ball in a premium set is sometimes more difficult because each ball is individually calibrated.
Keeping a Pool Ball Set Intact
Pool ball maintenance is an important part of keeping a table clean. That said, regular cleaning will not do much to protect the balls except, perhaps, preserve the gloss. However, this does not mean that you should neglect the set entirely.
It’s best to store your balls safely back in the box or on a rack. Doing so organizes them, making it less likely to lose one during a move or room reconfiguration.