Mineral Photos - Phosphate Rock

Background

Phosphate rock is used for its phosphorus content. Hennig Brand discovered the element phosphorus in 1669. He prepared it in a set of experiments on urine; each experiment used at least 50 to 60 buckets! Phosphorus is a very important piece of the DNA and RNA molecules of which all life is formed. It is also important for the development of teeth and bones. The name phosphorus comes from the Greek word phosphoros, which means bringer of light. Phosphorus is mined in the form of phosphate rock.

Phosphate rock is formed in oceans in the form of calcium phosphate, called phosphorite. It is deposited in extensive layers that cover thousands of square miles. Originally, the element phosphorus is dissolved from rocks. Some of this phosphorus goes into the soil where plants absorb it; some is carried by streams to the oceans. In the oceans the phosphorus is precipitated by organisms and sometimes by chemical reaction. Phosphorus-rich sediments alternate with other sediments (geologists say these beds are interstratified). Phosphorus-rich beds usually have very few fossils; however, deposits in Florida and North Carolina contain a large amount of marine fossils. Some geologists believe that the formation of these phosphorus layers occur under a very special condition in which no other type of sediment is present. In addition, it is believed that phosphorus-rich rock is deposited in a body of water in which there is no oxygen; this is called an anaerobic environment. Many theories say that phosphorus is absorbed by ocean plants that die. As they decompose, the phosphorus accumulates. Despite many theories, studies about the formation of phosphate rock continue and theories about its deposition are developing.



In addition to the sedimentary phosphate deposits, there are some igneous rocks that are also rich in phosphate minerals. Sedimentary phosphate deposits, however, are more plentiful.

Sources

Large deposits of phosphate from igneous rock are found in Canada, Russia, and South Africa. Deep-sea exploration of the world’s oceans has revealed that there are large deposits of phosphates on the continental shelf and on seamounts in the Atlantic and Pacific Oceans. Recovering these deposits, however, is still too expensive, so they remain untouched for now. In the United States, phosphate rock is mined in Florida, North Carolina, Utah and Idaho. Florida and North Carolina account for approximately 85% of phosphate rock production in the United States. U.S. companies export large quantities of phosphate fertilizers all over the world. Phosphate rock is imported to the United States as well. Nearly all of these imports come from Morocco, a major supplier of phosphate rock to the world.

Uses

Some phosphate rock is processed to recover elemental phosphorus. Pure phosphorus is used to make chemicals for use in industry.



The most important use of phosphate rock, though, is in the production of phosphate fertilizers for agriculture. Some is used to make calcium phosphate nutritional supplements for animals.



Substitutes and Alternative Sources

Phosphorus is so important to life, that there is no substitute for it in agriculture. As for alternative sources, the phosphorus deposits on the ocean floor may one day be recovered when a profitable method of deep ocean mining is developed.

PHOSPHATE ROCK

PHOSPHATE ROCK

(Data in thousand metric tons unless otherwise noted)

Domestic Production and Use: Phosphate rock ore was mined by 6 firms at 12 mines in 4 States and upgraded to an estimated 26.1 million tons of marketable product valued at $1.3 billion, f.o.b. mine. Florida and North Carolina accounted for more than 85% of total domestic output; the remainder was produced in Idaho and Utah. Marketable product refers to beneficiated phosphate rock with phosphorus pentoxide (P2O5) content suitable for phosphoric acid or elemental phosphorus production. More than 95% of the U.S. phosphate rock mined was used to manufacture wet-process phosphoric acid and superphosphoric acid, which were used as intermediate feedstocks in the manufacture of granular and liquid ammonium phosphate fertilizers and animal feed supplements. Approximately 45% of the wet-process phosphoric acid produced was exported in the form of upgraded granular diammonium and monoammonium phosphate (DAP and MAP, respectively) fertilizer, and merchant-grade phosphoric acid. The balance of the phosphate rock mined was for the manufacture of elemental phosphorus, which was used to produce phosphorus compounds for a variety of food-additive and industrial applications.

Salient Statistics—United States: 2006 2007 2008 2009 2010e

Production, marketable 30,100 29,700 30,200 26,400 26,100

Sold or used by producers 30,200 31,100 28,900 25,500 28,300

Imports for consumption 2,420 2,670 2,750 2,000 2,100

Consumption1 32,600 33,800 31,600 27,500 30,400

Price, average value, dollars per ton, f.o.b. mine2 30.49 51.10 76.76 127.19 50.00

Stocks, producer, yearend 7,070 4,970 6,340 8,120 5,800

Employment, mine and beneficiation plant, numbere 2,500 2,500 2,600 2,550 2,300

Net import reliance3 as a percentage of

apparent consumption 7 14 4 1 15

Recycling: None.

Import Sources (2006–09): Morocco, 100%.

Tariff: Item Number Normal Trade Relations

12-31-10

Natural calcium phosphates:

Unground 2510.10.0000 Free.

Ground 2510.20.0000 Free.

Depletion Allowance: 14% (Domestic and foreign).

Government Stockpile: None.

Prepared by Stephen M. Jasinski [(703) 648-7711, sjasinsk@usgs.gov, fax: (703) 648-7757]

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PHOSPHATE ROCK

Events, Trends, and Issues: In 2010, phosphate rock consumption and trade increased worldwide after depressed market conditions in 2008 and 2009. U.S. production was about the same as in 2009, as companies attempted to lower stocks of phosphate rock that had accumulated over the previous year. Domestic phosphoric acid and phosphate fertilizer production increased over that of 2009. The world spot price of phosphate rock began 2010 around $90 per ton and increased in the third quarter to around $150 per ton.

A new 3.9-million-ton-per-year phosphate rock mine in northern Peru began operation in July. The leading U.S. phosphate rock producer acquired a 35% share of the joint venture between the Brazilian and Japanese owners of the mine. The U.S. company will have the right to purchase up to 35% of the annual phosphate rock output to supplement its domestic phosphate rock production.

A new 5- million-ton-per-year phosphate rock mine began operation in Saudi Arabia late in 2010. The associated phosphate fertilizer plant was to open in 2011. World mine production capacity was projected to increase to 228 million tons by 2015 through mine expansion projects in Algeria, Brazil, China, Israel, Jordan, Syria, and Tunisia, and development of new mines in Australia, Kazakhstan, Namibia, and Russia.

World Mine Production and Reserves: Significant revisions were made to reserves data for Morocco, using information from the Moroccan producer and a report by the International Fertilizer Development Center. Reserves information for Russia was revised using official Government data and may not be comparable to the reserves definition in Appendix C. Reserves data for Algeria, Senegal, and Syria were revised based on individual company information.

Mine production Reserves4

2009 2010e

United States 26,400 26,100 1,400,000

Algeria 1,800 2,000 2,200,000

Australia 2,800 2,800 82,000

Brazil 6,350 5,500 340,000

Canada 700 700 5,000

China5 60,200 65,000 3,700,000

Egypt 5,000 5,000 100,000

Israel 2,700 3,000 180,000

Jordan 5,280 6,000 1,500,000

Morocco and Western Sahara 23,000 26,000 50,000,000

Russia 10,000 10,000 1,300,000

Senegal 650 650 180,000

South Africa 2,240 2,300 1,500,000

Syria 2,470 2,800 1,800,000

Togo 850 800 60,000

Tunisia 7,400 7,600 100,000

Other countries 8,620 9,500 620,000

World total (rounded) 166,000 176,000 65,000,000

World Resources: Domestic reserves data were based on U.S. Geological Survey and individual company information. Phosphate rock resources occur principally as sedimentary marine phosphorites. The largest sedimentary deposits are found in northern Africa, China, the Middle East, and the United States. Significant igneous occurrences are found in Brazil, Canada, Russia, and South Africa. Large phosphate resources have been identified on the continental shelves and on seamounts in the Atlantic Ocean and the Pacific Ocean.

Substitutes: There are no substitutes for phosphorus in agriculture.

eEstimated.

1Defined as phosphate rock sold or used + imports.

2Marketable phosphate rock, weighted value, all grades.

3Defined as imports – exports + adjustments for Government and industry stock changes.

4See Appendix C for resource/reserve definitions and information concerning data sources.

5Production data for China do not include small artisanal mines.

U.S. Geological Survey, Mineral Commodity Summaries, January 2011

http://minerals.usgs.gov/minerals/pubs/commodity/phosphate_rock/mcs-2011-phosp.pdf

Reservoirs of Ancient Lava Shaped Earth

Geological history has periodically featured giant lava eruptions that coat large swaths of land or ocean floor with basaltic lava, which hardens into rock formations called flood basalt. New research from Matthew Jackson and Richard Carlson proposes that the remnants of six of the largest volcanic events of the past 250 million years contain traces of the ancient Earth's primitive mantle -- which existed before the largely differentiated mantle of today -- offering clues to the geochemical history of the planet.

Scientists recently discovered that an area in northern Canada and Greenland composed of flood basalt contains traces of ancient Earth's primitive mantle. Carlson and Jackson's research expanded these findings, in order to determine if other large volcanic rock deposits also derive from primitive sources.

Information about the primitive mantle reservoir -- which came into existence after Earth's core formed but before Earth's outer rocky shell differentiated into crust and depleted mantle -- would teach scientists about the geochemistry of early Earth and how our planet arrived at its present state.

Until recently, scientists believed that Earth's primitive mantle, such as the remnants found in northern Canada and Greenland, originated from a type of meteorite called carbonaceous chondrites. But comparisons of isotopes of the element neodymium between samples from Earth and samples from chondrites didn't produce the expected results, which suggested that modern mantle reservoirs may have evolved from something different.

Carlson, of Carnegie's Department of Terrestrial Magnetism, and Jackson, a former Carnegie fellow now at Boston University, examined the isotopic characteristics of flood basalts to determine whether they were created by a primitive mantle source, even if it wasn't a chondritic one.

They used geochemical techniques based on isotopes of neodymium and lead to compare basalts from the previously discovered 62-million-year-old primitive mantle source in northern Canada's Baffin Island and West Greenland to basalts from the South Pacific's Ontong-Java Plateau, which formed in the largest volcanic event in geologic history. They discovered minor differences in the isotopic compositions of the two basaltic provinces, but not beyond what could be expected in a primitive reservoir.

They compared these findings to basalts from four other large accumulations of lava-formed rocks in Botswana, Russia, India, and the Indian Ocean, and determined that lavas that have interacted with continental crust the least (and are thus less contaminated) have neodymium and lead isotopic compositions similar to an early-formed primitive mantle composition.

The presence of these early-earth signatures in the six flood basalts suggests that a significant fraction of the world's largest volcanic events originate from a modern mantle source that is similar to the primitive reservoir discovered in Baffin Island and West Greenland. This primitive mantle is hotter, due to a higher concentration of radioactive elements, and more easily melted than other mantle reservoirs. As a result, it could be more likely to generate the eruptions that form flood basalts.