German alchemist Hennig Brand discovered what chemical element in 1669?

The discovery of phosphorus, the first element to be discovered that was not known since ancient times, is credited to the German alchemist Hennig Brand in 1669, although other chemists might have discovered phosphorus around the same time. Brand experimented with urine, which contains considerable quantities of dissolved phosphates from normal metabolism. Working in Hamburg, Brand attempted to create the fabled philosopher's stone through the distillation of some salts by evaporating urine, and in the process produced a white material that glowed in the dark and burned brilliantly. It was named phosphorus mirabilis ("miraculous bearer of light").

Phosphorus is a chemical element with symbol P and atomic number 15. As an element, phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Earth. At 0.099%, phosphorus is the most abundant pnictogen in the Earth's crust. With few exceptions, minerals containing phosphorus are in the maximally oxidized state as inorganic phosphate rocks.