Crystal composition

The chemical composition is silicon dioxide, and the chemical molecular formula is SiO2, which can contain trace impurities such as iron, manganese, magnesium, aluminum and titanium.

It belongs to the tripartite crystal system. Crystal is a collection of hexagonal columns, diamonds or hexagonal bipyramids. Cylinders have transverse grains, and aggregates are often crystal clusters. Most crystals are colorless and transparent, and those containing impurities can be purple, yellow, pink, brown, gray and black. Good transparency, crystal surface glass luster, fracture grease luster. The refractive index is 1.544- 1.533, the birefringence is 0.008, and the dispersion is 0.0 13. Purple crystal has dichroism. Hardness 7, density 2.66g/cm3. Shell fracture.