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.

Ghost-like low relief crystals become iridescent when viewed between crossed polars.
Ghost-like low relief crystals.
Decolorized zones concentrate around tiny crystals in this sapphire from Afghanistan’s Badakshan region.
The surfaces of these negative crystals are glossy and smooth, showing signs of heating in this Sri Lankan sapphire.
C-shaped crystals with faint growth zoning in the background of this sapphire from Madagascar. Irregular crystals such as this are a common sight in Madagascar sapphire.
‘Scuse me while I pierce the sky. A negative crystal cuts through a fingerprint against a sky blue backdrop in this unheated Sri Lanka sapphire.
Cluster of small zircon crystals in an untreated purple sapphire from Madagascar. Heat treatment will cause such crystals to become cloudy and more white as the temperature increases. Such zircon crystals are one of the hallmarks of Madagascar sapphires from the central and southern part of the island.
Undissolved rutile silk makes a lovely surprise in this unheated sapphire from Sri Lanka.
Kaolinite-bearing negative crystals flattened in the basal plane within a purple sapphire from Madagascar. The kaolinite aslo shows up in the infrared spectrum.
A classic scene in a Sri Lankan sapphire, where a secondary “fingerprint” surrounds a primary negative crystal. The basal pinacoid faces feature triangular growth markings, while the interior contains two v-shaped diaspore needles and black plates of graphite.
Elongated negative crystal in a yellow sapphire from Sri Lanka.
Undissolved rutile silk glitters in this untreated sapphire from Rubyvale, Austrlia.

Search the Complete Hyperion Database

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.