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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.
It is used as a defense against herbivores by at least 40 green plants in Australia, Brazil, and Africa; [43] other biologically synthesized organofluorines include ω-fluoro fatty acids, fluoroacetone, and 2-fluorocitrate. [50] In bacteria, the enzyme adenosyl-fluoride synthase, which makes the carbon–fluorine bond, has been isolated. The ...
Fluorine is a relatively new element in human applications. In ancient times, only minor uses of fluorine-containing minerals existed. The industrial use of fluorite, fluorine's source mineral, was first described by early scientist Georgius Agricola in the 16th century, in the context of smelting.
Two commercially important halide minerals are halite and fluorite. The former is a major source of sodium chloride, in parallel with sodium chloride extracted from sea water or brine wells. Fluorite is a major source of hydrogen fluoride, complementing the supply obtained as a byproduct of the production of fertilizer. Carnallite and ...
Amethyst crystals – a purple quartz Apophyllite crystals sitting right beside a cluster of peachy bowtie stilbite Aquamarine variety of beryl with tourmaline on orthoclase Arsenopyrite from Hidalgo del Parral, Chihuahua, Mexico Aurichalcite needles spraying out within a protected pocket lined by bladed calcite crystals Austinite from the Ojuela Mine, Mapimí, Durango, Mexico Ametrine ...
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 ...
Fluorite of the acidspar grade is used directly as an additive to ceramics and enamels, glass fibers and clouded glass, and cement, as well as in the outer coating of welding rods. [5] Acidspar is primarily used for making hydrofluoric acid, which is a chemical intermediate for most fluorine-containing compounds.
The CDC recommends water fluoridation at a level of 0.7–1.2 mg/L, depending on climate. The CDC also advises parents to monitor use of fluoride toothpaste, and use of water with fluoride concentrations above 2 mg/L, in children up to age 8. [32] There is a CDC database for researching the water fluoridation status of neighborhood water. [33]