What kind of crystal is a good crystal?

The surface of rock crystal ornaments is oily, while the surface of synthetic crystal ornaments is glassy, and there is no oily synthetic crystal. Therefore, the crystal with oily luster is a better crystal.

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1, crystal is a rare mineral and gem, which belongs to the seasonal family in mineralogy. Its main chemical composition is silicon dioxide, and its chemical formula is SiO2. When it is pure, it forms colorless and transparent crystals, and when it contains trace elements such as aluminum and iron, it is purple, yellow and brown. After irradiation, trace elements form different types of color centers and produce different colors, such as purple and Fe.

2. Inclusions containing associated inclusion minerals are called inclusion crystals, such as frosted crystals and green ghosts. Inclusions include rutile, tourmaline, actinolite, mica and chlorite. When the silicon dioxide crystal is perfect, it is a crystal; The imperfect crystallization is timely: crystal glue-dehydrated silica is agate; Water-containing silica gel becomes opal after solidification; When the particle size of silica is less than several microns, chalcedony, flint and secondary quartzite are formed.