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.

An iridescent dagger lances the heart of this sapphire from Myanmar’s Mogok Stone Tract.
Heat-altered fingerprint in a heat-treated yellow sapphire from Sri Lanka. Note the small burst clouds around the fingerprint channels.
This image clearly illustrates what master photomicrographer John Koivula has termed “chromophore cannibalization.” As titanium is drawn out of solid solution to form exsolved rutile silk, the area in the vicinity is decolorized, losing its blue color. This is a natural process and is the reverse of “internal diffusion,” where heat treatment sends the titanium back into solution, creating blue clouds or “inkspots” around the rutile remnants.
Surface-conformal color rim in a Madagascar pink sapphire that was diffused with beryllium to give it the appearance of a padparadscha sapphire.
Thin layer of iron-rich silk in a yellow sapphire from Chanthaburi, Thailand. This type of silk is typically found in green layers on the skin of the crystal and thus after cutting, is generally found just under the table and/or culet.
Thin layer of iron-rich silk in a yellow sapphire from Chanthaburi, Thailand. This type of silk is typically found in green layers on the skin of the crystal and thus after cutting, is generally found just under the table and/or culet.
Green color zone in a yellow sapphire from Chanthaburi, Thailand. This type of zoning is typically found on the skin of the crystal and thus after cutting, is generally found just under the table and/or culet. Careful examination often reveals thin patches of iron-rich silk in these green zones.
One of the more unusual inclusions we have encountered in sapphires from Nigeria’s Mambilla area are these deep red crystals. They are unlike anything we’ve seen in sapphires from other localities and are currently under investigation to determine their identify.
Kashmir cloud scene in natural Kashmir sapphire. These fine clouds, which are so small that they have never been definitively identified, are responsible for the famous velvet texture of these Himalayan blues. 15x.
A small crystal leaves a trail in its wake within this sapphire from Madagascar.
A lovely fingerprint explodes with iridescent color when illuminated obliquely with a fiber-optic light. The rectilinear healing pattern of this liquid inclusion reveals that it lies along a prism face (parallel to the c axis).

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