Black Beauty a coal slag abrasive, is too dusty and dirty for economical use.

Arm & Hammer / ARMEX baking soda comes with an additive / flow aid to prevent clogging in humid environments, detergent or additional abrasive where desired, etc.

Carbo-Jet is an alternative abrasive to baking soda being a pure white, fine crystal abrasive of neutral pH slightly more aggressive than baking soda, but will not dissolve in water.

As above, plastic blast media is available in a variety of materials and grit sizes
12-16, 12-20, 16-20, 20-30, 20-40, and 30-40.

BCS also stocks Garnet in a variety of grit sizes for water jet cutting and wet blasting.