Fluorspar is the commercial name for fluorite, a form of calcium fluoride (CaF2). Pure fluorite contains 51.3% calcium and 48.7% fluorine.
Fluorite is the primary source of fluorine, however relatively minor sources of fluorine include cryolite (Na3AlF6), sellaite (MgF2), topaz (Al2SiO4[F,OH]2), villiaumite (NaF), bastnasite ([Ce,La][CO3]F), and fluorapatite (Ca 5[PO4,CO3]3F).
Naturally occurring cryolite, used in the aluminium smelting process, has largely been replaced by synthetic cryolite.
Fluorspar may be found in a range of geological environments, such as hydrothermal and sedimentary, associated with barytes, calcium carbonate, galena, pyrite, quartz and sphalerite.
Fluorspar grades are categorised on the basis of CaF2 content. Major grades produced include:
Other grades include:
Another source of fluorine is fluosilicic acid (FSA), made as a by-product from the processing of phosphate rock into phosphoric acid for the fertiliser industry. FSA for its fluorine content has primarily been used as a water additive, particularly in the USA.
The world's identified resource of fluorspar is approximately 500m tonnes contained. However, if reserves of fluorine present in phosphate rock are also considered, then this adds a further 1.29bn tonnes of fluorspar (or 630m. tonnes of fluorine).
South Africa is the single largest holder of these reserves (18%) with 41m tonnes of fluorite reserves, followed by Mexico (14%) with 32m tonnes, China (9%) reporting 21m tonnes, and Mongolia (5%) having 12m tonnes.
Nearly 49% of the reserves are not commercially mined or produced.
World fluorspar production capacity is about 6.3m tpa (2012), and is dominated by China (50%) and Mexico (18%), followed by smaller production in Mongolia (7%) and South Africa (3%). Countries including Russia, Namibia and Spain account for 2% each, while Kenya and Morocco contribute 1% individually.
World's major fluorspar producers include:
Steyuan Mineral Resources Group China
Mongolrostsvetmet LLC Mongolia/Russia (JV)
Kenya Fluorspar Kenya
Vergenoeg Mining Company South Africa
Masan Resources Vietnam
British Fluorspar United Kingdom
There are two principal grades of fluorspar, which are defined based on the CaF2 content of the material. Metallurgical (and ceramic) grade fluorspar contains ≤97% CaF2, while acid grade fluorspar contains ≥97% CaF2.
Metspar is primarily sold as a flux into markets for iron and steel casting and steelmaking.
Source: Ray Will, IM Fluorspar Conference 2011
Acidspar is the raw material for hydrofluoric acid (HF) and thus for all fluorochemicals, in addition to being an important feedstock for aluminium fluoride (captive) and other markets (such as welding rods).
Around 60% of fluorspar produced in 2008 was classed as acid grade, with the balance classed as metallurgical grade.