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The term fluorspar refers to crude or beneficiated (extracted) material that
is mined and/or milled for the mineral fluorite (calcium fluoride). It is the
common commercial term used to describe concentrates of fluorite sold as metallurgical
grade (97 percent or less calcium fluoride) or acid grade (more than 97 percent
calcium fluoride).
Although fluorite has been used for ornamental purposes since ancient times,
it was not until the end of the 15th century that Basilius Valentinus, and later
Georgius Agricola in 1529, recorded its earliest use as a flux. In this case,
a flux is a substance that lowers the melting temperature of a material. Agricola
named fluorite for the Latin word “fluere” meaning to flow, and the
term was first formally used by mineralogist J.D. Dana in 1868. Fluorite is
a nonmetallic mineral, containing 51.1 percent calcium and 48.9 percent fluorine.
No fluorspar production occurred in the United States in 2002, but the United
States was a major producer of fluorspar from World War II until the late 1960s.
Competition first from Europe, then from Mexico and finally from China forced
the cessation of all fluorspar mining in the United States. The Ozark-Mahoning
Company in southern Illinois was the last major mining operation and it closed
in late 1995.
In 2002, reported U.S. fluorspar consumption was 588,000 metric tons, of which
533,000 tons was acid grade and 55,000 tons was metallurgical grade. Most acid-grade
fluorspar goes toward making hydrofluoric acid and aluminum fluoride; these
two uses accounted for nearly 90 percent of acid-grade consumption in 2002.
The major use for hydrofluoric acid is in the manufacture of various fluorocarbon
chemicals that are used as refrigerants, foam-blowing agents, solvents and in
the production of high-performance plastics. Most aluminum fluoride is used
in aluminum smelting, where it is added to the molten bath of cryolite and fluorspar
to lower the operating temperature, and to suppress the creation of sodium,
which reduces production efficiency. Metallurgical-grade fluorspar is consumed
primarily as a flux for steelmaking, but may also be consumed in cement, enamels,
glass and fiberglass, iron and steel castings, and welding rod coatings. U.S.
demand for fluorspar is met by imports, sales from the National Defense Stockpile
and byproduct calcium fluoride recovered from industrial waste streams. Currently,
the United States imports almost all its fluorspar from China, South Africa
and Mexico.
World fluorspar production was 4.51 million tons in 2002. China is by far the
world’s largest fluorspar producer; in 2002, it produced about 2.45 million
tons or 54 percent of total world production. China is also the world’s
largest exporter; it exported 1.0 million tons of fluorspar in 2002. Other significant
producing countries, in descending order and share of world production, were
Mexico (14 percent), South Africa (5 percent), Mongolia (4 percent) and Russia
(4 percent).
Because the largest use of hydrofluoric acid is in the production of fluorocarbon
chemicals, the phaseout of the first generation of fluorocarbons (chlorofluorocarbons
or CFCs) has had a negative effect on world demand for fluorspar. In 1989, world
production of fluorspar reached an all-time high, which coincidentally was the
year the Montreal Protocol on Substances that Deplete the Ozone Layer was ratified.
By 1994, as a result of the phaseout of CFCs, fluorspar production had decreased
by more than 32 percent. As more ozone-friendly fluorocarbon compounds (many
of which actually contain more fluorine than the CFCs they are replacing) have
been developed, fluorspar production has recovered somewhat but it still remains
about 19 percent below the 1989 peak.
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