One of the very early manufactured compounds of potassium was potassium carbonate,
known from biblical days as lye and used to prepare soap by reaction with animal fat.
It was produced by leaching wood ashes with water and concentrating the extract to a lye
solution by boiling. Probably because of the method used to prepare it, potassium carbonate
was known as potash; subsequently, however, the term potash was used to designate
potassium salts that were mined from large natural deposits, particularly where the
potassium compound was to be used as a necessary ingredient of fertilizer. In 1839, large
deposits of potash were discovered at Strassfurt, Germany, and played a major role in the
development of the early German chemical industry.