Potash () is some of various mined and manufactured salts that contain potassium in water-soluble form. The name derives from pot ash, which refers to plant ashes soaked in water in a pot, the primary means of manufacturing the product before the industrial era. The word potassium is derived from potash.Potash is produced worldwide at amounts exceeding 90 million tonnes (40 million tonnes K2O equivalent) per year, mostly for use in manufacturing. Various types of fertilizer-potash thus constitute the single largest industrial use of the element potassium in the world. Potassium was first derived in 1807 by electrolysis of caustic potash (potassium hydroxide).