It occurs as a mineral niter and is a natural solid source of nitrogen. It can be made by combining ammonium nitrate and potassium hydroxide.
The most famous use of potassium nitrate is probably as the oxidizer in blackpowder.
It is also used as fertilizers as a source of nitrogen and potassium. It is also used in some toothpaste for sensitive teeth. Also used in the treatement of asthama.
APPEARANCE WHITE TO OFF WHITE CRYSTLINE POWDER