Phosphate Rock as a Fertilizer

Ground phosphate rock is not classified as a fertilizer in most countries and is not included in fertilizer consumption statistics reported by most countries. However, FAO reports consumption of ground rock phosphate separately in 1976 reported consumption was 

Considerable difference of opinion exists as to the merits of ground rock phosphate as a fertilizer. In some countries, the chemical phosphate fertilizer industry perceives ground rock as a threat to its prosperity and has urged government restrictions of its use. In other cases, industry or government authorities have promoted its use. 

The main purpose of the latter policy is to enable much less costly sources of phosphate rock to be brought into use. This plays an important role in countries with large reserves of phosphate rock, but with inadequate finandal resources to invest in industrial production of phosphoric acid, TSP, and ammonium phosphates. 

Some of the factors that contribute to the difficulty of making an impartial appraisal of the merits of direct application of ground rock phosphate are  

Phosphate rocks vary widely in their reactivity hence their agronomic value varies. 

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