crystal history

Crystal glass or leaded glass is a type of silicate glass that contains lead oxide in its composition. This type of glass has a shiny appearance and is similar to quartz crystals, and the reason for its labeling seems to be the same. Glass containing more than 24% by weight of lead oxide is called crystal glass. But crystal glass usually contains 24 to 32 percent by weight of lead oxide. Another major component of crystal glass is SiO2. Sodium oxide and potassium oxide are also used in the composition of crystal glass.

The presence of lead in crystal glass increases the refractive index of light in this type of glass, and as a result, crystal glass has luster and luster. These glasses also have a low hardness and it is possible to shave these glasses. Therefore, decorative utensils called crystal utensils are made of this material. Also, because lead is an element with a high atomic mass, the density of glass containing lead is higher than other types of glass. Crystal glass also has a low elastic modulus, resulting in a rusty sound from impact. The word crystal has Greek roots and means “frozen by the cold.” The Greeks used crystal to refer to the mountain door. They believed that if water was kept at very low temperatures for a while, it would become stable at high temperatures. “Crystal” is also the root of “crystallization”. The first reference to the regular arrangement of crystal particles is found in the works of the famous astronomer J. Kepler (1619) and Robert Hook (1665), the discoverer of the microscope. Some time later, the famous scientist Christian Hughes (1690) examined the optical properties of calcite crystals (CaCO3) and proposed the hypothesis that crystals are made of very small particles with a specific shape. After that, M.V. Omonosov (1711-1765) completed the particle theory of material structure. He assumed that the particles were spherical in shape.

39 دیدگاه در “crystal history

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