warrant. 1  authorization, sanction, or justification. 2  something that serves to give reliable or formal assurance of something; guarantee, pledge, or security. 3  something considered as having the force of a guarantee or as being positive assurance of a thing: The cavalry and artillery were considered sure warrants of success.
Potassium metal was discovered in 1807 in England by Sir Humphry Davy, who derived it from caustic potash (KOH), by the use of electrolysis of the molten salt with the newly discovered voltaic pile. Before the 18th century, no distinction was made between potassium and sodium.
Potassium carbonate, which was gathered from wood ash, was concentrated through boiling and then used for industrial purposes, such as soap making. The wood ash origin of the potassium carbonate lent the name potash to the compound (and eventually to the element). Potassium was first isolated by Sir Humphrey Davy in 1807. He used electrolysis with a dry potash compound to identify the element. He would later use this same process to isolate sodium, which was previously undistinguished from potassium.