I. Overview of gold deposits The atomic number 79 of gold , the element symbol Au, is derived from the Latin Aurnm, meaning the dawn, the metaphorical sun. Gold has only one natural stable isotope 197, which is an equiaxed crystal at room temperature and a vertical lattice. Naturally good crystal forms are extremely rare, often in the form of irregular granules, agglomerates, flakes, reticular, dendritic, fibrous and spongy aggregates. Gold as gold, containing impurities, the color range change occurs, when silver or platinum color fades, the copper-containing darken. When the streak of gold on the test plate is reddish, the color is high; when it contains 10% silver, the streak is golden yellow; when it contains 20-30% of silver, it is grass yellow; when the content of silver exceeds 30%, it has yellow With a green hue; silver containing more than 50% is silvery white. Gold is chemically stable and has strong corrosion resistance. It is generally not oxidized from normal temperature to high temperature. Gold insoluble in common acids and bases, but can be dissolved in aqua regia, an alkali metal cyanide, an acidic thiourea solution, bromine solution, boiling solution of ferric chloride, the presence of oxygen, potassium, sodium, calcium, magnesium Thiosulfate solution, etc. Sulfides of alkali metals corrode gold to form soluble gold sulfide. Humic acids in the soil and metabolites of certain bacteria can also dissolve trace amounts of gold. Gold having thiophilic, often intimately associated with the sulfides such as pyrite, arsenopyrite, galena, stibnite, and the like; and easily thiophilic silver, palladium, platinum, copper, nickel, mercury, bismuth, antimony, 铑 and 铱 form an intermetallic compound. Gold has a pro-iron nature, and gold in strontium iron is three orders of magnitude higher than normal rock. Copper and silver are concentrated in the sulfide phase; while gold and platinum are concentrated in the metal phase. The abundance of gold in the core is 2.6 ppm, the mantle is 5 ppb, and the crust is 1.8 ppb. More than 99% of the gold on the earth enters the core. Therefore, the abundance of gold formed in the early stage of the development of the earth is relatively high. Therefore, the Archean greenstone belt, especially the combination of mafic and ultramafic volcanic rocks, has a higher abundance of gold than the various types of rocks in the earth's crust. Due to the low abundance of gold in the earth's crust, it has the characteristics of sulfophilicity, pro-copper, iron-producing, high melting point, etc., and the formation of industrial deposits requires thousands of times of enrichment. Mines generally have to undergo a fairly long geological period, which may be formed by multiple mineralization superpositions. Gold can exist in the three valence states of 0, +1 and +3 in nature, and can be produced in the form of independent minerals, isomorphisms and colloidal adsorption. To date, 98 gold minerals and gold-bearing minerals have been discovered in the world, but only 47 species are common, and only 10 minerals are directly used by industry. According to the principle of crystal chemistry, gold minerals and gold-bearing minerals can be divided into: (1) Natural elements and alloys of silver, palladium, platinum, copper, nickel, mercury, antimony, bismuth, antimony and bismuth are mineral gold (Au) containing Au>80%; silver gold ore (Au; Ag) ), containing Au 80% ~ 50%, Ag 20% ​​~ 50%; gold and silver ore (Au; Ag), containing Au 50% ~ 20%, Ag 50% ~ 80%, containing platinum palladium natural gold, silver copper gold mine, Weishan Mine, Sifang copper and gold mine, black gold mine Au2Bi. (2) Gold-silver bismuth minerals include bismuth gold ore, bismuth gold and silver ore, and acupuncture gold and silver ore. (3) Gold, silver and selenide minerals are selenium gold and silver ore. (4) Gold and silver sulfide minerals are sulfur gold and silver ore. Natural gold (silver gold ore, etc.) can be divided into clear gold (>0.1mm), microscopic gold (0.1mm-0.25μm), sub-microscopic gold (0.25μm-2nm), and sub-electron diffraction gold according to its particle size. -0.288 nm). There is a kind of natural gold that is eye-catching, that is the dog's head gold. The dog's head gold is naturally produced, the texture is impure, the grain is large and the irregular shape is gold. It usually consists of natural gold, quartz and other mineral aggregates. Because it looks like a dog's head, it is called a dog's head gold; like a horseshoe, it is called a horseshoe gold. In the middle of the 19th century, a carpenter picked up a dog's head gold on the west coast of the United States, weighing 32kg, which opened the gold rush in California. A caravan in Australia was turned over by the stone when passing through the gold mining area. The check-in was actually a huge dog's head gold weighing 77.6kg. So far, the world has found that more than 10kg of dog's head gold is about 8,000 to 10,000, especially in Australia, accounting for 80% of the total amount of dog's head gold, the largest of which weighs 235.87kg. The total amount of dog's head gold found in China is about a thousand. In 1909, when the Yanyuan gold mining workers in Sichuan were working underground, they were unfortunately dropped from the top of the "stone" and injured their feet. They moved the "stone" to the mouth of the pit and saw it was a piece of gold weighing 31 kg. In 1982, in the Heilongjiang Province, Huma Xinglong Township, Jin Jingong, Yue Shuchen, encountered a piece of gold weighing 3325g when he was planing. In 1983, Wang Bojun, a farmer from Zhengwudangqiao Village in southwestern Shaanxi, picked up a piece of 810g of doghead gold. Konglonggou, Baiyu County, Sichuan Province, found large gold nuggets weighing 4800.8g and 6136.15g in 1987. At 6:30 pm on June 7, 1997, the 13th gold mining team of the Menyuansigou Gold Mine in Qinghai discovered a large stone gold nugget weighing 6577g on the sand gold chute. Shibaojin is a form of dog's head gold. From the point of view of the dog gold that has been discovered, there are generally three forms, namely, gold, stone, gold and gold. Regardless of the specimen world, in the personal collection world, the valuation of this natural gold is extremely high. Gold deposits can be produced in almost any type of rock and in any age, but the Precambrian greenstone belt is the most important. The mineralization types of gold are: greenstone belt type (including basic and ultrabasic rocks), volcanic rock type, porphyry type (including alkaline rock, granite ), turbidite type, black rock series, glutenite type , river sediment type; divided by genetic types of quartz vein, sulfide vein type, micro-disseminated, structural alteration type, Fe, Mn hat, clay type. Second, how to find gold mines? 1. First, attention should be paid to silicified zones, quartz veins, and secondary quartzites . This is because gold mineralization is closely related to silicidation. It can be said that no silicon is not gold. Of course, not all siliceous bodies produce gold, but most of the gold-containing siliceous bodies are smoky and have good water color. This is because the gold-containing siliceous bodies all contain more or less sulfides, and because the sulfides are extremely fine, the quartz is smoky. In particular, sheet-like quartz veins (which may contain a plurality of black strips such as a mixture of carbonaceous and fine-grained sulfides) have good gold content. Even less bright gold sulfide quartz veins, when the package to gold, there is often the presence of antimony sulfides such as brightness, bismuthinite, bournonite, arsenopyrite, roe-like lead zinc ore. 2. Focus again on the fractured structural belt, especially the ductile shear zone. Gold mineralization is all related to faults, and it can be said that there is no structure. In particular, attention should be paid to super-tribes, mylonites, micro-sweet-like quartzites, and talc magnesite schists, which are often rich in gold ore bodies. The gold-bearing properties of the giant to large fault zones are often poor, while the secondary secondary fault zones are often the gold ore bodies. 3. The third is to pay attention to the gold-bearing property of the iron cap, maroon, brownish yellow residual slope and carbonate leaching tank deposits. They can not only become iron cap type, laterite type gold mines, but also indicate the search for primary gold mines. 4. The fourth thing to note is to find gold in the areas of antimony, mercury, and arsenic (especially the realgar or ore). In the case of antimony ore, it can be symbiotic with gold to form a gold deposit; it can also be separated, but Not far from each other, there is a saying that "not in it, not leaving it." The periphery of some lead-zinc mines can also be found in gold, such as the periphery of the Qingchengzi lead-zinc mine; the lower part of the copper deposit. The copper-nickel sulfide deposit alteration zone is also a good place to find gold. 5, related to the alteration in addition to gold silicide, and iron dolomitization, calcite of iron, chromium of white mica, pyrite phyllic, feldspar of ice, fine-grained pyrite, arsenic, antimony, Low temperature alteration combination of mercury, antimony and antimony mineralization. 6. Focus on the fractured fracture zone and its tectonic alteration zone in basic rock, ultrabasic rock, lamprophyre, alkaline rock, alkaline granitic rock, carbon-silica argillaceous rock, impure carbonate rock . 7. Carry out the work of river heavy sand, ditch system secondary halo and various geochemical methods. It is the most important method for gold search. 8. Find gold according to the indicator element of finding gold. For example, the combination of elements such as mercury, antimony, bismuth, arsenic, antimony, selenium, lead, zinc, copper and silver is abnormally gold. 9. Indirectly search for gold deposits by means of geophysical methods to find out the structure of faults and the distribution of sulfides. These serives provides high performance filtration products for high, medium and low pressure hydraulic applications. Our expertise extends to virtually any hydraulic, fuel, lubrication, coolant, or pneumatic system found on an aircraft. Some of our Hydraulic Filter supply to The Boeing company and domestic military factory. We continue to refine an integrated product team approach to the design, development and qualification of state of the art filtration systems and flow control devices. This method, which includes close technical collaboration with the customer, often results in consultation in preliminary and conceptual design of filtration systems on new aircraft applications with our customers. Water Filter,Nature Gas Filter,Air Medium Filter,Liquid Cooling Filter XINXIANG PINGYUAN AVIATION HYDRAULIC EQUIPMENTS CO.,LTD , https://www.coupling.pl