sapphire treatments

Nearly all sapphires used in jewelry have undergone some sort of treatment.  The type of treatment, and to what extent, will affect the value of the sapphire.

Over 95% of sapphires have been heated to improve their appearance.  Heating is commonly used to improve color and can also improve clarity by altering, or even eliminating, unattractive inclusions.

Scroll down for inclusion photos.

heat treated sapphires

discoid fracture

Discoid fracture in a heat treated sapphire
Photo courtesy of GGTL Laboratories

Oval or circular tension halos surrounding an included crystal that expanded during heat treatment, causing a fracture in the sapphire.

partially healed fingerprint

Several fingerprint inclusions inside a natural sapphire
Photo courtesy of Scott Papper, GIA GG, AJP, CM (NAJA), Global Gemology & Appraisals

When exposed to high temperatures, the networks of tiny, liquid-filled tubes begin to resorb.

lattice diffused sapphires

Lattice diffused sapphire shows color concentrations at facet junctions
Photo courtesy of Scott Papper, GIA GG, AJP, CM (NAJA), Global Gemology & Appraisals

A process using heat and chemicals diffuses an element into the sapphire, permanently changing its color.

Color concentrations can be found at the facet junctions when submerged, in diffused lighting.​