Any of various commercial phosphate fertilizers obtained as white to gray granules or powders by acidulating ground insoluble phosphate rock, such as: (1) a product made by acidulating with sulfuric acid, consisting essentially of primary calcium phosphate, calcium sulfate, and smaller quantities of secondary calcium phosphate, and containing usually about 20% of available phosphoric acid; or (2) a product made by acidulating with phosphoric acid, consisting essentially of primary calcium phosphate and containing usually 40% to 50% of available phosphoric acid.