Mineral Resource of the Month: Phosphate

By Stephen M. Jasinski, USGS mineral commodity specialist

Phosphate rock ore concentrate. Credit: U.S. Geological Survey. Phosphate rock ore concentrate. Credit: U.S. Geological Survey.



Phosphate rock refers to unprocessed ore and beneficiated concentrates that contain some form of apatite, a group of calcium phosphate minerals. Apatite in phosphate rock is the primary source for phosphorus in phosphate fertilizers. More than 80 percent of the world’s current production of phosphate rock is mined from sedimentary deposits, which were formed by the deposition of phosphate-rich materials in marine regions. Most of the rest comes from igneous deposits of carbonatites and silica-deficient intrusions. The grade of phosphate rock is classified by the phosphorus pentoxide content.


Credit: K. Canter, AGI. Credit: K. Canter, AGI.


Credit: K. Canter, AGI. Credit: K. Canter, AGI.



Credit: K. Canter, AGI. Credit: K. Canter, AGI.


Credit: K. Canter, AGI. Credit: K. Canter, AGI.

 Most phosphate is used to produce fertilizer. Credit: USDA/NRCS. Most phosphate is used to produce fertilizer. Credit: USDA/NRCS.


  • Worldwide, more than 85 percent of the phosphate rock mined is used to manufacture phosphate fertilizers. The remaining 15 percent is used to make elemental phosphorus and animal feed supplements, or it is applied directly to soils. Treating phosphate rock with sulfuric acid makes phosphoric acid, a water-soluble material and the basic material from which most phosphatic fertilizers are derived. Elemental phosphorus is produced by smelting phosphate rock, coke and silica in an electric furnace. Elemental phosphorus is used to manufacture a wide range of chemical compounds.


  • Phosphate rock is used to make phosphate compounds that are used in applications such as food additives, detergents and herbicides. Phosphoric acid is used in cola beverages.
  • Phosphorus was first discovered in 1669 by Hennig Brand in Germany, when he recovered it from urine.

Visit minerals.usgs.gov/minerals for more information

design by K. Cantner and N. Schmidgall, AGI

 Credit: United States Geological Survey. Credit: U.S. Geological Survey

 Credit: The American Geosciences Institute. Credit: American Geosciences Institute



U.S. Geological Survey

The "Mineral Resource of the Month" column is written by various U.S. Geological Survey mineral commodity specialists. For more information about these and other mineral commodities, visit: USGS Commodity Statistics and Information.

Tuesday, October 23, 2018 - 06:00

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