Chalk

Cue tip chalk (invented in its modern form by straight rail billiard pro William A. Spinks and chemist William Hoskins in 1897)^[13][14] is made by crushing silica and the abrasive substance corundum or aloxite^[14] (aluminiumoxide),^[15][16] into a powder.^[14] It is combined with dye (originally and most commonly green or blue-green, like traditional billiard cloth, but available today, like the cloth, in many colors) and a binder (glue).^[14] Each manufacturer's brand has different qualities, which can significantly affect play. High humidity can also impair the effectiveness of chalk. Harder, drier compounds are generally considered superior by most players.