Diamond refers to polished diamond, which is a natural mineral and the original stone of diamond. Simply put, diamond is a simple crystal composed of carbon element formed under high pressure and high temperature conditions in the deep part of the earth. Diamonds are beautiful and rare. They are symbols of love and loyalty, representing eternal love.
On May 17 and 16, Sotheby's held a spring jewelry auction in Geneva, Switzerland. A pair of colored pear-shaped diamond earrings set a new record in the auction history with a total price of about 57.4 million US dollars (about 395 million yuan). This pair of pear-shaped earrings is made in South Africa. Except for the different colors, the appearance is almost the same, weighing about 16 carats respectively. Among them, the dark pink diamond named "Artemis" fetched US$ 6.5438+0.55 million (RMB 6.5438+0.067 million), and the other diamond was deep lake blue, named "Apollo", because its color is rarer than pink diamonds, and its price is more than twice that of pink diamonds.
The chemical composition of diamond is carbon, which is the only single element in gem and belongs to equiaxed crystal system. It often contains 0.05%-0.2% impurity elements, of which N and B are the most important, and their existence is related to the types and properties of diamonds. Its crystal forms are mostly octahedron, rhombic dodecahedron, tetrahedron and their aggregates. Pure diamond is colorless and transparent, showing different colors due to the mixing of trace elements. Strong diamond luster. The refractive index is 2.4 17 and the dispersion is moderate, which is 0.044. An isotropic object. The thermal conductivity is 0.35 calories/cm/sec/degree. Tested by thermal conductivity meter, the response is the most sensitive. The hardness is 10, which is the hardest mineral known at present. The absolute hardness is 1000 times that of the time, and 150 times that of corundum. It is afraid of heavy blows, and it will be broken by cleavage after heavy blows. A set of cleavage is completed. The density is 3.52g/cm3. Diamonds are luminous, and after being irradiated by sunlight, they can emit light blue phosphorescence at night. X-ray irradiation emits sky blue fluorescence. The chemical properties of diamond are very stable, and it is not easy to dissolve in acid and alkali at room temperature, and acid and alkali will not affect it.