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At least 17,000 metric tons of fluorine are produced each year. It costs only $5–8 per kilogram as uranium or sulfur hexafluoride, but many times more as an element because of handling challenges. Most processes using free fluorine in large amounts employ in situ generation under vertical integration. [186]
Fluorite mining (the main source of fluorine) was estimated in 2003 to be a $550 million industry, extracting 4.5 million tons per year. [4] Mined fluorite is separated into two main grades, with about equal production of each. Acidspar is at least 97% CaF 2; metspar is much lower purity, 60–85%.
Graphs of abundance vs atomic number. Abundance (atom fraction) of the chemical elements in Earth's upper continental crust as a function of atomic number; [5] siderophiles shown in yellow. Graphs of abundance against atomic number can reveal patterns relating abundance to stellar nucleosynthesis and geochemistry.
Fluorine is primarily carried by rivers to the oceans, where it can have a residence time of about 500,000 years. Fluorine can be removed from the ocean by deposition of terrigenous or authigenic sediments, or subduction of the oceanic lithosphere. The fluorine cycle is the series of biogeochemical processes through which fluorine moves through ...
Fluorite (CaF 2), also called fluorspar, is the main source of commercial fluorine. Fluorite is a colorful mineral associated with hydrothermal deposits. It is common and found worldwide. China supplies more than half of the world's demand and Mexico is the second-largest producer in the world. [citation needed] The United States produced most ...
As a result, the physical and chemical properties of organofluorines can be distinctive in comparison to other organohalogens. The carbon–fluorine bond is one of the strongest in organic chemistry (an average bond energy around 480 kJ/mol [ 1 ]). This is significantly stronger than the bonds of carbon with other halogens (an average bond ...
Fluorine biology is also relevant to a number of cutting-edge technologies. PFCs (perfluorocarbons) are capable of holding enough oxygen to support human liquid breathing. Organofluorine in the form of its radioisotope 18 F is also at the heart of a modern medical imaging technique known as positron emission tomography (PET).
Fluorite (also called fluorspar) is the mineral form of calcium fluoride, CaF 2. It belongs to the halide minerals. It crystallizes in isometric cubic habit, although octahedral and more complex isometric forms are not uncommon. The Mohs scale of mineral hardness, based on scratch hardness comparison, defines value 4 as fluorite.