Sapphire Inclusions

First Published: 7 September 2026

Sapphire Inclusions

Explore sapphire inclusions in Hyperion, the Lotus Gemology inclusion database. Hyperion contains photomicrographs of inclusions and internal features in natural sapphire, documented with information on geographic origin, treatment, lighting conditions, field of view, photographer and published references.

The melted, shiny fissure around this small crystal represents clear evidence that the sapphire host has been heat treated.
These brown crystals (probably phlogopite mica) show no signs of heat damage in their Sri Lankan sapphire host.
These brown crystals (probably phlogopite mica) show no signs of heat damage in their Sri Lankan sapphire host.
Often chalky shortwave fluorescence is a sign of heat treatment in sapphire, but some stones from Madagascar, like this one, show a superficially chalky patch that is not associated with heat treatment.
A crystal filled with an unknown yellow substance stands out against its sapphire-blue background.
Chalky shortwave fluorescence follows the pattern of partially dissolved silk in this heated pink sapphire.
Iridescent fissures around small crystals create a floral motif in this heated sapphire.
Streams of fine particles zig-zag across this heated sapphire.
The high temperatures reached during beryllium diffusion have produced melted surfaces on a natural.
Magnification of this beryllium-diffused orange sapphire reveals small areas on the surface where corundum has melted and recrystallized. This is sometimes seen in beryllium-diffused corundums, due to the high temperatures reached during the treatment.
When immersed in di-iodomethane, this orange sapphire reveals a surface-conformal color rim, exposing it as having been beryllium diffused.
This bright orange sapphire shows no evidence of heat treatment in the microscope, but the chalky zoned shortwave ultraviolet fluorescence quickly unmasks the fact that the stone had been heated.

Sapphire inclusions may include mineral crystals, rutile silk, healed fissures, fluid inclusions, negative crystals, color zoning and other features formed during or after crystal growth. Such features are important to gemologists because they can provide evidence useful in identifying sapphire, understanding its geological history, recognizing treatment and, in some cases, determining geographic origin.

Sapphire Inclusion Photomicrographs

The Hyperion sapphire gallery includes microscopic features found in sapphires from major deposits around the world. Each entry is accompanied by descriptive information and, where available, references to the gemological literature.

What Inclusions Can Reveal About Sapphire

Inclusions are an important part of sapphire identification. Their form, composition, orientation and alteration can help gemologists distinguish natural sapphire from synthetic material, recognize evidence of heat treatment, and study the geological environment in which the sapphire formed.

Hyperion combines inclusion photomicrography with supporting gemological information so that individual features can be compared with documented examples from known sapphire deposits.

About Hyperion

Hyperion is the Lotus Gemology searchable inclusion database. It allows users to browse gemstone inclusions by gem type, geographic origin, treatment and keyword.

Search the Complete Hyperion Database