[Chemical composition] often contains Hf, Th, U, TR and other mixed substances, when some of the mixed substances reach a certain content, many varieties can be formed. Such as Yamaguchi Stone (TR 2 O 3 1093%; P 2 O 5 177%), hydrozircon (water content is generally 3% to 10%), Quartz (containing higher TR and U, radioactive crystal face bending named), hafnium rich zircon (HfO 2 up to 24%) and the like. Since zircon usually contains Th and U, the absolute age of zircon and its parent rock can be determined by measuring the content of Th/U in zircon and the ratio of their lead isotope and their ratio to U. . Since Pb elements are difficult to enter the zircon lattice, and U and Pb are strongly fractionated during zircon crystallization, zircon is a good U-Pb isotopic dating object. In addition, more and more studies have shown that the zircon ring-like hyperplasia is very common, combined with the micro-region dating method can reflect the geological evolution process corresponding to the zircon growth history. Zircon is also a very reliable "pressurevessel" that holds the wrap from its parent rock or early metamorphism. At the end of the 20th century, a series of conservative metamorphic belts for zircon testing and micro-regional dating were carried out in a number of controversial metamorphic belts (Vavra et al., 1996, Herman et al., 2001, Katayama et al., 2001). [Crystal structure] tetragonal system; [Form] The crystal has a tetragonal double-cone shape, a columnar shape, a plate shape (Fig. G-1), and can be formed into a knee-shaped twin crystal according to (011). Figure G-1 Crystals of zircon (Where (a), (b), (c), (d), (e) are quoted from Pan Zhaoyu, 1993, (f) according to Zhao Shanrong, produced in the cavern of the Kuiqi rock mass in Fujian) Square column: m{110}, a{100}; quadrilateral double cone: p{111}, u{331}; complex quadrilateral double cone: x{311} The morphology of zircon is singular. For example, in the alkaline rock, the zircon quadrangular cone {111} is very developed. In the acidic rock, the zircon quadrangular and the square column {100}, {110} More developed, the crystal shape is columnar; in basic rocks, neutral rocks or partial-base granites , the zircon cylinders develop and the cones are relatively undeveloped, sometimes not even appearing, but sometimes {311} Complex square biconical. In addition, the formation conditions can also be judged by using the zircon crystal aspect ratio and roundness. [Physical Properties] in color, and its related components changeable; glass just to gold luster, fracture oil sheen; transparent to translucent. The cleavage is incomplete, which is also related to the uniform distribution of the bond strength in the structure; the fracture is not flat or shell-like. Hardness 7.5 ~ 8. The relative density is 4.~4. Crisp. When zircon contains a relatively high amount of radioactive elements such as Th and U, it is radioactive and often causes amorphization. Compared with ordinary zircon, the transparency is reduced, and it can be opaque; the gloss is dim; the relative density and hardness are lowered ( H = 5); the refractive index decreases and is in a homogeneous state. [genesis and occurrence] Zircon is a subsidiary mineral widely distributed in acidic and alkaline magmatic rocks. In basic and neutral rocks Also produced. In pegmatite, zircon is often closely associated with rare elemental minerals. It is also common in sedimentary rocks and metamorphic rocks. Zircon is rich in ore in alkaline rock, such as the giant zircon deposit produced in the nepheline syenite in southern Norway. In addition, due to the stable nature of zircon, it can be integrated into sand ore. [identification characteristics] is characterized by its crystal shape, large hardness, and diamond luster. The difference from rutile is that the hardness is large, there is no {110} complete cleavage, no Ti reaction; the difference from cassiterite is that the relative density of zircon is small, and the cassiterite has Sn reaction. [Main use] The main mineral raw materials for extracting zirconium and hafnium are bright and transparent, and can be used as gem materials. Due to its high temperature resistance, corrosion resistance, high mechanical strength, ability to absorb gases and absorb neutrons, metallic zirconium is widely used in industrial and defense-critical technologies. Zircon can be used as an opacifier in the ceramic industry, which not only can improve the opacity, but also improve the glaze hardness, whiteness, abrasion resistance and prevent glaze cracking; in addition, with the rare earth elements contained in zircon It is also possible to generate yttrium oxide , yttrium oxide, etc. to improve the thermal stability, dielectric properties, mechanical strength, and the like of the product. Polycarbonate Diffuser,Polycarbonate Light Diffuser,Opal Polycarbonate Diffuser,Lexan Diffuser Jiangmen Kunxin new Material Technology Co.,Ltd , https://www.jmkunxinplastics.com
a 0 =0.662 nm, c 0 =0.602 nm; Z=4. In the structure, the [SiO 4 ] tetrahedron is isolated and bonded to each other by Zr 4 ; and the two are arranged in the c-axis direction. The coordination number of Zr 4+ is 8, which is a [ZrO 8 ] coordination polyhedron which is specially distorted by a cube. The entire structure can also be considered as a combination of a [SiO 4 ] tetrahedron and a [ZrO 8 ] polyhedron.
Zr[SiO 4 ]