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.

A cluster of negative crystals appears to pierce the center of this sapphire.
This negative crystal in sapphire contains what are likely a dark graphite platelet and diaspore needles insdie.
A small, chalky fluorescent patch can be observed when carefully examining this heated yellow sapphire in short wave UV illumination.
In the “We thought we had seen it all” department, this unusual inclusion was found on the polished girdle of an untreated Madagascar sapphire. We believe it to be made up of growth marks on the surface of the original sapphire crystal.
This basalt-related sapphire contained many crystal inclusions that were all oriented parallel to the basal plane. Notice how the fissures around each crystal are all aligned.
When we examine this sapphire from Sri Lanka, the euhedral crystal pictured here stood out immediately. Analysis with micro Raman confirmed that the crystal is apatite.
Ensconced between fingerprints and negative crystals in this sapphire is a green spinel crystal, which was identified with micro Raman.
Between crossed polars, this apatite crystal (identified with micro Raman) displays bright interference colors.
The healing pattern of this healed fissure in a Sri Lankan sapphire suggests it lies along a pyramid face, oblique to the c-axis. Should it lie perpendicular to the c-axis, the healing would reveal triangular or hexagonal healing; if parallel to the c-axis, the healing would be rectangular. Thus the nearly rectangular healing reveals its orientation along a pyramid face close to the c-axis. The use of oblique illumination reveals far more surface detail than ordinary dark or light field.
The angular chalky reaction, observable with short wave illumination, provides clear evidence that this blue sapphire was heated.
This elongated rose channel in a blue sapphire shows signs of heat treatment, with a series of glassy fissures visible across the stone. In the background we can observe many thin-film decrepitation halos.
A series of thin-film decrepitation halos decorates the interior of this blue sapphire.

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