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Pure fluorite is colourless and transparent, both in visible and ultraviolet light, but impurities usually make it a colorful mineral and the stone has ornamental and lapidary uses. Industrially, fluorite is used as a flux for smelting, and in the production of certain glasses and enamels.
The main uses of fluoride, in terms of volume, are in the production of cryolite, Na 3 AlF 6. It is used in aluminium smelting. Formerly, it was mined, but now it is derived from hydrogen fluoride. Fluorite is used on a large scale to separate slag in steel-making. Mined fluorite (CaF 2) is a commodity chemical used in steel-making.
The fluorite structure refers to a common motif for compounds with the formula MX 2. [1] [2] The X ions occupy the eight tetrahedral interstitial sites whereas M ions occupy the regular sites of a face-centered cubic (FCC) structure. Many compounds, notably the common mineral fluorite (CaF 2), adopt this structure.
Naturally occurring CaF 2 is the principal source of hydrogen fluoride, a commodity chemical used to produce a wide range of materials. Calcium fluoride in the fluorite state is of significant commercial importance as a fluoride source. [11] Hydrogen fluoride is liberated from the mineral by the action of concentrated sulfuric acid: [12]
Others, such as the fluorite group, are not water-soluble. As a collective whole, simple halide minerals (containing fluorine through iodine, alkali metals, alkaline Earth metals, in addition to other metals/cations) occur abundantly at the surface of the Earth in a variety of geologic settings. More complex minerals as shown below are also ...
Though elemental fluorine (F 2) is very rare in everyday life, fluorine-containing compounds such as fluorite occur naturally as minerals. Naturally occurring organofluorine compounds are extremely rare. Man-made fluoride compounds are common and are used in medicines, pesticides, and materials.
Yttrium(III) fluoride has a refractive index of 1.51 at 500 nm [4] and is transparent in the range from 193 nm to 14,000 nm (i.e. from the UV to IR range).. Pure yttrium can be obtained from yttrium(III) fluoride by reduction with calcium.
Fluorite, the primary mineral source of fluorine, which gave the element its name, was first described in 1529; as it was added to metal ores to lower their melting points for smelting, the Latin verb fluo meaning ' to flow ' gave the mineral its name. Proposed as an element in 1810, fluorine proved difficult and dangerous to separate from its ...