[Chemical composition] Common elements such as Co and Ni are substituted for Fe in the same type, and Au and Ag are commonly mixed mechanically. [crystal structure] equiaxed crystal system; Figure L-26 Pyrite crystal (quoted from Pan Zhaoyu et al., 1993) [Form] Commonly intact crystal form, in the form of a cube {100}, a pentagonal dodecahedron {210} or an octahedron {111}. Three sets of mutually perpendicular crystal fringes are often seen on the cubic crystal plane. The direction of the stripe is perpendicular to each other on the two adjacent crystal planes, which is consistent with the symmetry type (Fig. L-27(a)). In addition, interspersed twin crystals can also be formed, and the iron cross (see Figure L-27(e)) aggregates are often dense, loose, granular, and tuberculous (Figure L-28). Figure L-27 Pyrite crystal (quoted from Pan Zhaoyu et al., 1993) Cube: a{100}; pentagonal dodecahedron: e{210}; octahedron: o{111} Figure L-28 Pyrite crystal aggregate [Physical properties] a pale yellow copper surface with cinnamon Qiang color; Green Black streak; strong metallic luster, opacity. No cleavage; the gap is jagged. Hardness 6 to 6.5. The relative density is 4.9 to 5.2. Crisp. [genesis and production] Pyrite is the most widely distributed sulfide in the crust, formed under a variety of different geological conditions. (1) It is produced in a copper- nickel sulfide magma deposit and is characterized by being rich in Ni. (2) Produced in contact with meta-mineral deposits, often containing Co. (3) Produced in a polymetallic hydrothermal deposit, the content of Cu, Zn, Pb, Ag, etc. in the pyrite component is increased. (4) In the deposits related to volcanism, the content of As and Se in pyrite components increased. (5) exogenous causes of pyrite found sedimentary rocks and sedimentary deposits of coal layer, and tends to agglomerate into nodular. Under surface oxidation conditions, pyrite is easily decomposed to form various iron sulfates and hydroxides. Among the iron sulfates, jarosite is the most common; iron hydroxide is the most common of goethite, which is the main mineral component of limonite. Limonite is sometimes an illusion of pyrite. [identification characteristics] According to its crystal shape, crystal fringe, color, hardness and other characteristics can be distinguished from similar chalcopyrite and pyrrhotite. [Main use] It is also used as a main mineral raw material for the production of sulfuric acid, and can also be used for the extraction of sulfur. When it contains Au, Ag or Co, Ni, it can be comprehensively utilized. Chaff Cutter Machine,Silage Chaff Cutter Machine,Chaff Cutter Chopper Machine,Chaff Feed Cutter Machine HUNAN JINSONG MACHINERY CO., LTD , https://www.sheller.nl
; a 0 = 0.542 nm; Z = 4. Pyrite derived structure of NaCl type structure (Fig L-26), galena crystal structure similar to that of the dumbbell-shaped sulfide [S 2] 2- galena takes the place of the simple structure sulfide ions, Fe 2+ replaces the position of Pb 2+ . However, since the dumbbell-shaped direction of the sulfide ions is staggered in the structure, the bond forces in each direction are similar, so the pyrite cleavage is extremely incomplete and the hardness is significantly increased.
Pyrite
Fe[S 2 ]