The REE contents in apatites are useful in paleoceanographic studies to identify the seawater masses and circulation patterns or to quantify the redox state of the ocean. pharmaceuticals, ceramics, textiles and explosives) and represents an important alternative source of rare-earth elements (REE). Only 10 – 15% of the world’s production of phosphate rock has other applications (e.g. It is the only significant global resource of phosphorus used dominantly in the manufacturing of nitrogen-phosphorus-potassium (NPK) fertilizers for food-crop nutrition and in the production of animal feed supplements. The beneficiation products of apatite ores as a commodity are traded as phosphate rock. The average distribution of trace elements in phosphate rock. The magmatic ores are generally of lower grade but give higher-quality beneficiation products with low contents of unwanted contaminants (Cd, Pb, As, U, Th, Mg and Al). The igneous deposits comprise fluorapatite ores, which mostly accommodate carbonatites and other types of alkaline intrusions. The former comprises the stratiform phosphorite deposits in shelf-type shale-carbonate sequences, which contain high phosphorus ores of microcrystalline CO 2-rich fluorapatite (francolite) and cryptocrystalline collophane. However, exploitable deposits of apatite are mainly found in igneous rocks and also in sedimentary and metamorphic rocks. According to the list of symbols for rock- and ore-forming minerals, the abbreviated symbol used for apatite is Ap. On the Earth’s surface, primarily because it is stable in a wide variety of geological conditions and over a range of different geological processes. Phosphorus is the 10th most abundant element on Earth, with an average crustal abundance of 0.1%. Also, much of phosphorus in coal is present in the form of apatite. Apatite is found in all classes of rock: igneous, metamorphic and sedimentary. Apatite is the most abundant phosphate mineral, which accounts for more than 95% of all phosphorus in the Earth’s crust and is found as an accessory mineral in most rock types 1Ī rock may be best defined as any mineral or aggregate of minerals that forms an essential part of the Earth.
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