Purple sapphire is a rare variety of corundum displaying hues ranging from pale lavender purple to intense violet. Its captivating color is primarily caused by traces of vanadium in its crystal structure.
9硬度（满分10）
Corundum所属矿物族
Heat TreatmentHeat treatment is very common for purple sapphires. It improves color by removing unwanted secondary tones and intensifying the purple. This treatment is permanent and widely accepted in the market.
Untreated (Natural)Untreated purple sapphires are rarer and typically command a price premium of 30 to 100% over heated stones of comparable quality. They should be accompanied by a certificate from a reputable laboratory (GIA, GRS, SSEF).
Diffusion TreatmentLess common treatment that introduces coloring elements at the surface or deeper. This treatment must be disclosed as it significantly affects the stone's value.
