The chemical composition of crystal is pure silica with a specific gravity of 2.66, which is very stable. W przeciwieństwie do innych klejnotów, which contain many other elements or contained substances, the specific gravity will be in a range. Its refractive index is 1.544～1.553. , The birefringence difference is 0.009, współczynnik dyspersji wynosi 0.013, i […]
