Potash, also known as potassium chloride, is the common term for fertilizer forms of the element potassium (K). The term is widely applied to naturally occurring potassium salts, and the commercial products that are developed from them. The name derives from the collection of wood ash in metal pots when the beneficial fertilizer properties of this material were first recognized many centuries ago.
Potash in Nature
Potassium occurs abundantly in nature. It is the 7th most common element in the earth’s crust. Certain clay minerals associated with heavy soils are rich sources of K, containing as much as 17% potash. Sea water typically contains 390 mg/L K representing a huge total amount of the element globally. Small quantities of K naturally occur in rain – up to 4 parts-per-million. Of course K in these forms is not economically extractable, and thus not yet used to produce the K required to meet global demand.
Large potash bearing deposits (rock or brine) occur in many regions of the world deriving from the minerals in ancient seas which dried up millions of years ago.