What is "phosphogypsum"

n. (context inorganic compound English) A form of gypsum (calcium sulfate) formed as a by-product in the manufacture of phosphate fertilizers

Phosphogypsum refers to the gypsum formed as a by-product of the production of fertilizer from phosphate rock. It is mainly composed of gypsum (CaSO·2HO). Although gypsum is a widely used material in the construction industry, phosphogypsum is usually not used, but is stored indefinitely because of its weak radioactivity. The long range storage is controversial.