Material: S925 Sterling Silver/ 6A Cubic Zirconia Main Stone type: 7*9mm We use high-grade zircon, compare to the low-grade zircon, the high grade zircon has higher dispersion, so the refractive index is stronger, so it is more shiny. And it has higher density, so it is more solid and wear resistant. And our high grade zircon products has great fire color.