What is the main ingredient of корунд?

The main component of corundum is aluminum oxide.

corundum, the name originated from India, is a mineralogical name. There are three main variants of the homogeneity of corundum Al2O3, namely α-Al2O3, β-Al2O3, and γ-Al2O3. The hardness of corundum is second only to diamond.

Corundum is a gemstone formed from the crystals of alumina (Al2O3). Corundum mixed with metallic chromium is bright red and is generally called ruby; while blue or colorless corundum is generally classified as sapphire.

Corundum ranks 9th in the Mohs hardness table. The specific gravity is 4.00, and it has a hexagonal column lattice structure. Because of its hardness and relatively lower price than diamonds, corundum has become a good material for sandpaper and grinding tools.

Corundum has glass luster, hardness 9. The proportion is 3.95-4.10. It is formed under the conditions of high temperature, rich aluminum and poor silicon C, and is mainly related to magmatism, contact metamorphism and regional metamorphism.

Corundum is a man-made material made from bauxite as the main raw material in a mining furnace. It can be used as abrasive and refractory material. The white corundum with higher purity is called white corundum, and the brown corundum with a small amount of impurities is called brown corundum.

There are mainly three variants of the homogeneity of corundum Al2O3, namely α-Al2O3, β-Al2O3, γ-Al2O3, and η-Al2O3 (equaxial crystal system) and ρ-Al2O3 (crystal system) according to X-ray diffraction analysis. The system is uncertain), χ-Al2O3 (hexagonal system), κ-Al2O3 (hexagonal system), δ-Al2O3 (tetragonal system), θ-Al2O3 (monoclinic system). Corundum has many colors, including colorless, white, golden (pigment ion Ni, Cr), yellow (pigment ion Ni), red (pigment ion Cr), blue (pigment ion Ti, Fe), green (pigment ion Co, Ni) , V), purple (Ti, Fe, Cr), brown, black (pigment ion Fe, Fe), blue-violet under incandescent lamp, red-purple effect under fluorescent lamp (pigment ion V).