Natural Ruby Inclusions

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

While superficially the rutile silk in this ruby may look intact, closer observation reveals that some of the needles have started to break down and develop gaps. Other evidence in the stone confirmed that this ruby was heated.
A melted fingerprint with drippy edges provides evidence that this ruby was heated.
A chalky appearance can be observed in this heated ruby. Note that the chalky areas follow the pattern of silk.
A cluster of prismatic crystals, resembling primary rutile, with delicate silk needles extending nearby.
A cluster of prismatic crystals, resembling primary rutile, penetrates the stone’s surface with a luster brighter than that of the host.
Tiny thin films hide under the girdle of this ruby from Baringo, Kenya.
Iridescent fissures illuminate the interior of this ruby. These fissures typically form along the rhombohedron faces and result from external (secondary) pressures after the crystal formed. The same pressures produce polysynthetic glide twinning.
This Thai/Cambodian ruby displays thin films with drippy, irregular edges and a melted crystal inclusion featuring an immobile gas bubble. These features act as evidence that the stone has been heat treated.
A sprinkle of rutile silk in this Mozambique ruby provides evidence that the stone is natural.
Unusual small “doily”-like flat inclusions in a ruby believed to originate from Mozambique’s Montepuez mine.
Red-orange crystals of primary rutile surrounded by small rounded grains of zircon believed to be from Mozambique. The identify of the inclusions was confirmed by microRaman (courtesy of GIA Bangkok). It was once thought that primary rutile and zircon were not found in Mozambique ruby, but the current evidence suggests that they are. In this photo shot in reflected light, two of the rutile crystals are cut through on the surface, displaying a much higher luster than the surrounding ruby.
Red-orange crystals of primary rutile surrounded by small rounded grains of zircon believed to be from Mozambique. The identify of the inclusions was confirmed by microRaman (courtesy of GIA Bangkok). It was once thought that primary rutile and zircon were not found in Mozambique ruby, but the current evidence suggests that they are.

Natural ruby 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 ruby, understanding its geological history, recognizing treatment and, in some cases, determining geographic origin.

Natural Ruby Inclusion Photomicrographs

The Hyperion natural ruby gallery includes microscopic features found in rubies 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 Natural Ruby

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

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