Potassium

Potassium (abbreviated as K) is an element. It is an essential nutrient for many plants and animals.

When burning plant matter, such as wood, the potassium remains in the ashes. As it is water soluble, the ashes can be soaked in water and filtered to just a liquid. The water is left to evaporate or boiled off, traditionally in a pot, and potassium crystals will start to form potash. When the element was discovered in potash, it was given the name potassium in reference to it.