Potash

Potash, potassium-based salts used in fertilizers. Most potash comes from the mineral sylvite and is often found in underground salt beds or in salt lakes. Potassium chloride (KCI) is the most important type of potash but another type, potassium carbonate (K₂C0₃), can be manufactured by running water through wood ashes and boiling the solution in large iron pots.