Check out the pictures for a better idea of condition. I don't believe this cue ball went to this set originally.
Vintage Regulation Size Billiard Pool Ball Set Complete W/ Red Dot Cue & Tray
Billiard Wholesalers Canada
Product description:-Comes in different design-Used to improve control over the ball-Precise roundness and balance-Made of high-quality resin
Red dot cue ball : r/billiards
FLORIDA GATORS Numbered Billiard Ball Set - SCHOOL COLORS
Why Do Cue Balls Have Red Dots? (Monitoring Ball Spin) - IndoorGameBunker
Source 2-1/4 Regulation Size Billiard/Pool Ball: Super Pro Cup Cue Ball with 6 Red Dots on m.
Super Aramith Pro Billiard Ball Set