Interestingly, elemental phosphorus was originally isolated from urine: https://en.wikipedia.org/wiki/Phosphorus#Discovery https://en.wikipedia.org/wiki/Phosph

Interestingly, elemental phosphorus was originally isolated from urine: https://en.wikipedia.org/wiki/Phosphorus#Discovery https://en.wikipedia.org/wiki/Phosphorus#Discovery which is funny considering that economists and such are worried that mining phosphorus rock might have a limit soon: https://en.wikipedia.org/wiki/Peak_phosphorus https://en.wikipedia.org/wiki/Peak_phosphorus