Chloro apatite

Lead oxy-, hydroxy-, and alkali-metal apatites, Pbio(P04)eO, Pbio(P04)s(OH)2, and Pb8M2(P04)g, show differences in their i.r, spectra, and new lead phosphates with apatite-type structures but low Pb P ratios have been obtained. -Ray data for twin crystals of cadmium chloro-apatite, Cd5(P04)3Cl, point to the compound being isostructural with fiuoroapatite and the problem of the twinning in these crystals is discussed in relation to structural details. ... 

Also neodymium lead chloro apatites have been synthesized and their crystals grown with the purpose of obtaining new laser materials (Grisafe and Hummel, 1970 Michel et al., 1975, Joukoff et al., 1978). They are prospective minilaser crystals (Guillot et al., 1980). The condensed phosphates have been evaluated, along with the borates, as hosts for Tb laser applications (Colak and Zwicker, 1983). 

Several hundred phosphate minerals (see Mineralogy) are known, virtually aU of which are orthophosphates An exception is Canaphite, CaNa2P20y dHyO. The important mineral Apatite, Cas(P04)3X is found in igneous pegmatite rocks and hydrothermal veins. Fluoro-, Chloro-, and Hydroxyapatites are found (X = F, Cl, OH, respectively) as well as many substituted varieties. 

Names apatite, calcium (fluoro, chloro, hydroxyl) phosphate... 

A variation of calcium phosphate is the major component of bones and teeth in all vertebrates including humans. These calcium phosphates are usually referred to collectively as biological apatites, which are nonstoichiometric compounds based on pure apatites, Ca5(P04)3X, where X can be fluorine (F), chlorine (Cl), or hydroxyl (OH). (These are called fluoro-, chloro-, and hydroxyapatite, respectively.) In biological apatites the calcium cations can be replaced with varying amounts of strontium, magnesium, sodium, and potassium ions, and the phosphate anions can be replaced with hydrogen phosphates and carbonates. 

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