Phosphate rock is the raw material now used in commercial fertilizer production. Phosphate rock is extracted from the earth in many countries. Most of the phosphate rock is used for fertilizer production, with smaller amounts going to various industrial uses.t is made from two common constituents in the fertilizer industry and it is popular because of its relatively high nutrient content and its excellent physical properties. • Monoammonium phosphate (MAP) – A widely used source of P and N, it is made of two constituents common in the fertilizer industry.