The most common source of phosphorous on Earth is in phosphate (PO4) form and found in rocks. Calcium phosphate is the most common form of phosphorus found naturally and is mined extensively throughout the world. Major mining deposits include North Africa, China, Florida, Russia, and Tennessee.
Elemental phosporus (P), that is to say phosphorus that is not bonded to any other atoms, is not found in nature due to its high reactivity. Elemental phosphorus can be produced from phosphate rock by heating it to 1500 C in the presence of sand and carbon to produce what is called white phosphorus. This material is extremely reactive to oxygen and air. Exposing white phosphorus to sunlight and heat produces red phosphorus, the other major form of elemental phosphorus. White and red phosphorus are both the same element (phosphorus) but they have different molcular configurations. As such they are allotropes of each other and have different properties as a result.