Aluminum ore mainly consists of diaspore, boehmite and gibbsite, all of which are ore for aluminum smelting. White or light gray, light green, light red due to impurities. Vitreous luster, cleavage surface pearl luster. Transparent to translucent. Hardness 2.5~3.5. The relative density is 2.30~2.43. Mud odor. Under a polarizer, it is colorless. Biaxial crystals. Ng=1.587, Nm=Np=1.566. divided into,

The diaspore is also known as diaspore, and its structural formula and molecular formula are AlO(OH) and Al2O3·H2O, respectively. Orthorhombic crystal system, those with intact crystals are columnar, plate-like, scaly, needle-like, prism-like, etc. Diabsite is soluble in acid and alkali, but it is very weak at normal temperature and pressure, and needs to be fully decomposed under high temperature and high pressure and strong acid or alkali concentration.

Boehmite, also known as boehmite and boehmite, has a structural formula of AlO(OH) and a molecular formula of Al2O3·H2O. Orthorhombic crystal system, with intact crystals in the form of rhombus, prismatic, prismatic, needle-like, fibrous and hexagonal. Boehmite is soluble in acids and bases. The mineral is formed in acidic media, mainly in sedimentary bauxite, and is characterized by symbiosis with siderite.

Gibbsite is also known as diaspore, hydroxyaluminite, the structural formula is Al(OH), and the molecular formula is Al2O3·3H2O. Monoclinic crystal system, those with intact crystals are hexagonal plates and prisms, often in the form of fine crystal aggregates or twin crystals, and gibbsite in the ore is mostly irregular aggregates. It is soluble in acids and alkalis, and its powder It can be completely dissolved by heating to 100℃ for 2h. This mineral is formed in acidic media. Its main uses are,

(1) Aluminum smelting industry. For national defense, aviation, automobiles, electrical appliances, chemicals, daily necessities, etc.

(2) Precision casting. The bauxite clinker is processed into fine powder to make a mold and then precision cast. For military, aerospace, communications, instrumentation, machinery.

(3) For refractory products. The high alumina bauxite clinker has a refractoriness higher than 1780℃, strong chemical stability and good physical properties.

(4) Aluminum silicate refractory fiber. It has the advantages of light weight, high temperature resistance, good thermal stability, low thermal conductivity, small heat capacity and mechanical vibration resistance. Used in steel, non-ferrous metallurgy, electronics, petroleum, chemical industry, aerospace, atomic energy, national defense and other industries. It is to put high-alumina clinker into a high-temperature electric arc furnace with a melting temperature of about 2000-2200 °C, and after high-temperature melting, high-pressure high-speed air or steam injection, and cooling, it becomes white "cotton" - aluminum silicate refractory fiber. It can be pressed into fiber blanket, board or woven into cloth to replace refractory bricks lining high temperature furnaces in smelting, chemical, glass and other industries. Firefighters can use fire-resistant fiber cloth to make clothes.

(5) Using magnesia and bauxite clinker as raw materials, adding appropriate binder, it is very effective for pouring the overall lining of the ladle.

(6) Manufacture of various compounds of alumina cement, abrasive materials, ceramic industry and chemical industry that can make aluminum.

The most important uses are: metal aluminum extraction in the aluminum industry, as refractory materials and abrasive materials, and as raw materials for high-alumina cement. Different uses of ore have different quality requirements. The industry standard for bauxite ore issued by China Nonferrous Metals Corporation in 1994 (YS/T78-94). According to this standard, bauxite is divided into three types: sedimentary diaspore, accumulation type diaspore and laterite gibbsite, and is divided into LK12-70, LK8-65, LK5- 60, LK3-53, LK15-60, LK11-55, LK8-50, LK7-50, LK3-40 and other nine grades. In addition to stipulating the chemical composition of bauxite, the standard also requires that the moisture content of sedimentary diaspore should not exceed 7%, and the moisture content of accumulated diaspore and laterite gibbsite should not exceed 8%. . In addition, it is required that the particle size of bauxite ore shall not be greater than 150mm. Bauxite ore shall not be mixed with soil, limestone and other debris.