In nature, phosphorous is found in the Earth's crust, ~0.12 % (w/w), in minerals such as chlorapatite, fluorapatite, vivianite, wavelite and phosphite . The isotope found in nature is 31P (100 %, stable) .
In pure solid form, phosphorous as P4 exist as:
α-form: cubic crystal at > -79.6 °C .
β-form: hexagonal crystal at < -79.6 °C .