World Mineral Production - NERC Open Research Archive - Natural ...

FLUORSPAR
Characteristics
Fluorspar is the commercial name for the mineral fluorite
(calcium fluoride, CaF2). The pure form consists of 51.1 per
cent calcium and 48.9 per cent fluorine. Fluorine represents an
average 0.06 to 0.09 per cent of the Earth’s crust and is mainly
found occurring in fluorite. It is also found in small amounts
in a wide variety of other minerals, such as apatite and
phlogopite. Fluorite generally occurs as well-formed cubic
crystals exhibiting a wide range of colours and usually
contains mineral impurities such as calcite, quartz, barytes,
celestite, various sulphides or phosphates. Commercial
fluorspar is graded according to quality and specification into
acid-grade (minimum 97 per cent CaF2), metallurgical grade
(minimum 80 per cent CaF2) and ceramic grade (80 – 96 per
cent CaF2 and up to three per cent SiO2). Fluorspar is found in a wide range of geological environments
on every continent. The primary economic source of fluorspar
is in vein deposits (sheet-like bodies formed by minerals
crystallising from aqueous solutions to fill fissures in rock)
where it occurs as the main mineral or with metallic ores, in
particular lead, zinc, silver and barytes. It also occurs as
replacement deposits, replacing limestone or marble. In vein
deposits fluorspar tends to occur as lenticular bodies, separated
by barren areas. The mineralised veins vary considerably in
width and length, usually being between 1 m to 10 m wide and
50 m to 500 m long
World reserves of fluorspar (measured as pure CaF 2) are 240
million tonnes (Mt), of which South Africa holds 41 Mt,
Mexico 32 Mt and China 21Mt (USGS, 2008).
The grade of fluorspar determines its end-use. Approximately
34 per cent of fluorspar produced worldwide is of
metallurgical grade and is used primarily as a flux in
steelmaking and in the production of aluminum. Ceramic
grade fluorspar is used in the production of glass and ceramics
as well as the manufacture of magnesium and calcium metal
and accounts for a very limited amount of worldwide
production. Around 65 per cent of fluorspar produced is acidgrade
fluorspar; this is used in the production of hydrofluoric
acid (HF), the basis for all fluorine-bearing compounds, which
include important pharmaceuticals and agrochemicals. One of
the largest uses of hydrofluoric acid was in the production of
chlorofluorocarbons (CFCs) but CFC production in recent
years has rapidly declined due to concern over the effect of the
chlorine component in depleting the ozone. To some extent
they have been replaced by hydrofluorocarbons (HFCs)
although these are classed as ‘greenhouse gases’ and their use
is strictly controlled. Acid grade fluorspar is also an important
component in plastics manufacture. Fluoropolomyers such as
Teflon® have high thermal stability, high chemical inertness,
strong electrical insulation and a low coefficient of friction and
so have many applications. A rapidly growing market is
nitrogen trifluoride (NF3) which is widely used as a cleaning
gas in the manufacture of semiconductors and LCD screens.
World production in 2006
World production in 2006 increased by eight per cent: a small
decrease from the nine per cent rise seen in 2005. There has
been steady growth in fluorspar production since 2003, driven
for the most part by increased Chinese consumption. China
also continued its dominance of world fluorspar production
with 54 per cent of the total. Chinese production increased by
11 per cent from 2005–2006 and has increased by 13 per cent
in the last five years. The world’s second largest producer,
Mexico, showed a production increase of seven per cent in
2006 and production has risen by 50 per cent since 2002. The
figures from the world’s third largest producer, South Africa,
were not so positive with a 10 per cent drop in production.
This was due to the country’s largest producer, Sallies,
experiencing delays on planning decisions for new mining
infrastructure, low recovery grades, equipment breakdowns
and heavy rains.
European production was stable, with the largest producers
Russia and Spain showing little or no change. French
production dropped by 25 per cent following the closure of
three mines in the Pyrenees due to depletion of reserves.
Italy’s sole fluorspar producer, Nuova Mineraria Silius, ceased
operations due to the end of government subsidies.
Prices
Over the last twelve months fluorspar prices have been stable
with only small increases in prices for certain grades. However
the average price in 2007 was 30 per cent more than the
average in 2006, continuing a steady pattern of growth since
2003. Mexican acidspar filtercake (f.o.b. Tampico), was priced
at US$180 – US$200 per tonne and Chinese acidspar
filtercake (c.i.f. US Gulf Port) was priced at US$305 and
US$310 per tonne in 2007. Higher Chinese prices were caused
in part by the raising of their export tax from 10 per cent to 15
per cent on 1 June.
Industry events in 2007
China continued a pattern of decreasing fluorspar exports in
2007, dropping the export quota by four per cent (USGS,
2008). This caused a shortfall of fluorspar in the world market
and pushed prices up. Several major fluorspar deposits
continued to undergo development in 2007. Minemakers of
Australia continued to develop the Moina skarn in Tasmania,
Australia’s largest fluorspar deposit, with an interim resources
estimate scheduled to be completed in 2008.
In South Africa, 2007 was a more positive year for Sallies,
owner of the Witkop mine, production increased with the
development of the Buffalo tailings operation and the
company is once again reported to be making a profit. Central
African Mining and Exploration Company (CAMEC) began a
feasibility study on the Doornhoek deposit, potentially the
world’s largest deposit.
In the UK Glebe Mines was taken over by Ineos Fluor. This
move should secure Ineos Fluor’s fluorspar supplies for
hydrofluoric acid (HF) manufacture and secure the UK’s
fluorspar and HF industries for the near future.
Selected bibliography
BACKUS, R. 2007. Sun rises on China’s fluorochemicals.
Industrial Minerals. November 2007, p42-51.
CLARKE, G. 2008. Feasting on fluorspar in Frankfurt.
Industrial Minerals. January 2008, p44–48.
CLARKE, G. 2007. Riding the fluorspar Rollercoaster.
Industrial Minerals Magazine, February 2007, p48–53.
INDUSTRIAL MINERALS. 2007. IM Prices. December 2007,
p76–77.
USGS. 2008. Mineral commodity summaries [online]. [cited
January 2008] Available from
http://minerals.usgs.gov/minerals/pubs/commodity/fluorspar/i
ndex.html#mcs
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