Potash, POT ash, is the commercial name for a group of salts containing the element potassium. The most important type of potash is potassium chloride (KCl), which is mainly used to make fertilizer. About 95 per cent of the potash that is processed throughout the world is refined for fertilizers. Potash is also used in the manufacture of soaps and detergents, glass, ceramics, textiles, dyes, chemicals, and drugs.