A mixture of single superphosphate and triple superphosphate is called double superphosphate. Previously grain, livestock, oil, salt, superphosphate and water was carried. CSBP commissioned superphosphate and sulphuric acid plants in Kwinana in 1967. Greene increased production by scientific use of superphosphate fertiliser, rotation between grazing and wheat fallowing. Their investigations also produced the "superphosphate", consisting in the acid treatment of phosphate rock. By 1871 there were about 80 factories making superphosphate. The ore was discharged at Fremantle and sent to the superphosphate works. More than 90% of a typical superphosphate fertilizer is water-soluble. Triple superphosphate (TSP) typically consists of 44-48% of PO and no gypsum. It was the first company in Australia to manufacture superphosphate. The fertilizers used on Cacao include Ammonium sulfate, Single superphosphate, Potassium sulfate, and Magnesium sulfate. They are used mainly as superphosphate fertilizers and are also popular leavening agents.. In December 1982 one of the planned GH conversions was reallocated to superphosphate traffic. Superphosphate fertilizers are produced by treatment of "phosphate rock" with acids.