Hint: The above so-called "definition of scientific and technical terms" is a one-sided definition limited to traditional Chinese medicine, and the definition given by the Encyclopedia of China - Traditional Chinese Medicine volume is exactly the same. However, for the "natural copper", China University of Geosciences Geological Digital Museum and the Chinese Encyclopedia - Geology Volume to give the definition is: natural copper, English copper, is the copper element in nature naturally occurring in a variety of flake, plate, block aggregate.
Natural copper is a variety of naturally occurring copper elements in nature flake, plate, block aggregate. The surface of unoxidized natural copper is red and has a metallic luster. However, because of oxidation, usually natural copper will be brownish black or green. Natural copper also tends to contain traces of iron, silver and gold. Copper is an important metal with a wide range of uses.
Primary natural copper often contains a small amount or trace Fe, Ag, Au, Hg, Bi, Sb, V, Ge and other elements; Fe in the 2.5% or less, Ag more natural silver inclusions, Au solid solution up to 2 ~ 3%. Secondary natural copper is more pure. The crystal structure belongs to the isometric crystal system. Crystals are cubic, pentagonal dodecahedral and octahedral crystals
Natural copper (raw)
shaped, in the cubic or pentagonal dodecahedral crystalline surface with stripes, adjacent to the two crystalline surfaces of the stripes perpendicular to each other. The aggregate is in the form of dense massive, infiltrated and globular nodules. The medicinal ones are mostly cubic. Light yellowish copper color, often with yellowish brown FOH color on the surface. Streaks greenish black. Strong metallic luster. Hardness 6 to 6.5, brittle. Relative density 49～52, no disintegration, fracture jagged. Pyrite is the most widely distributed sulfide in the earth's crust, can be seen in a variety of rocks and ores, but most of them are formed by volcanic deposits and volcanic hydrothermal action. The pyrite of external causes is found in sedimentary rocks, sedimentary ores and coal seams, and the pyrite formed here is mostly in the form of dense lumps and nodules. Produced in Liaoning, Hebei, Jiangsu, Anhui, Hubei, Hunan, Guangdong, Sichuan, Yunnan and other places. Pyrite is unstable in the oxidized zone, easily decomposed to form various iron sulfates and hydroxides. The iron hydroxide is limonite. while retaining the artifacts of pyrite. Individual areas in Yunnan, Guangdong and other provinces are about to use the pyrite that has changed into limonite called "Tulan Copper". Whether its efficacy is the same as pyrite is worth studying.
Isoaxial crystal system, Oh5-Fm3m; a0=0.361nm; Z=4. The atoms are cubic and most tightly stacked, located in the corner top of the cubic cell and the center of each face, constituting a copper structure arranged according to the cubic center. Hexa-octahedral crystal type, Oh-m3m (3L44L36L29PC). Intact crystals are rare. Main monomorphs: cubic a, rhombic dodecahedral d, octahedral o, and also tetrahexahedral h. Bicrystalline faces according to (111), simple contact bicrystals are common, and interspersed bicrystals are also present. The aggregate is often irregular dendritic, lamellar or twisted copper filaments, fibrous and so on. Secondary natural copper is mostly in the form of rough powder or flake, fine vein-like, dense block, etc.. It is the product of reducing conditions in geological action, formed in primary hydrothermal deposits; also seen in the lower part of the oxidation zone of copper-bearing sulfide deposits, often accompanied by hematite, malachite, chalcopyrite, etc., by the reduction of copper sulfide:
CuFeS2(Chalcopyrite) 4O2 ; CuSO4 FeSO4
2CuSO4 2FeSO4 H2O ; Cu2O( Chalcopyrite) Fe2(SO4)3 H2SO4
Cu2O H2SO4 ; CuSO4 H2O Cu(Natural Copper)
Natural copper is also sometimes accounted for as a colluvium in conglomerates and occurs in copper-bearing sandstones. Unstable under oxidizing conditions, often transformed into copper oxides and carbonates, such as hematite (Cu2O), black copper ore (CuO), malachite, bluish chalcopyrite and so on. Copper red, the surface often appears brownish-black oxidized film. Streak copper red. Metallic luster. Opaque. No solubility. Hardness 2.5~3. Relative density 8.4~8.95. ductile, good electrical and thermal conductivity. Microscopic: rose color, copper red. Reflectivity R: 61(green), 83(orange), 89(red).
[Identification Characteristics] Copper-red, surface oxide film brownish-black, dense, ductile. Often associated with malachite, blue chalcopyrite. Easy to melt in the blowpipe flame, the flame is green (Cu). Natural copper is commonly found in primary hydrothermal deposits, copper-bearing sulfide deposits in the lower part of the oxidation zone and sandstone copper deposits, it is a variety of geological processes under the reducing conditions
Products. Natural copper is unstable in the surface and oxidizing environment, easily transformed into copper oxides and carbonates, such as hematite, malachite, bluecopperite and other minerals.
The world's famous natural copper producing areas are the U.S. Upper Lake (Lake Superior), Russia's Turinsk and Italy's Montecatini. China's Hubei Daye, Yunnan Dongchuan, Jiangxi Dexing, Anhui Tongling, Sichuan Huili / and the middle and lower reaches of the Yangtze River and other places in the oxidized zone of copper deposits have output. The Jiuquwan copper deposit in Mayang County, Hunan Province, also has natural copper as the main copper mineral. Conservation unit: Geological Museum of China Image description: This is a photograph of a specimen of natural copper (Copper) from China. Copper yellow. Streak: copper red. Luster: metallic. Opaque. Resolution
Resolution: no resolution. Hardness: 2.5-3. Specific gravity: 8.5-8. Good electrical and thermal conductivity.
Preservation unit: China Geological Museum