Treated Ruby Inclusions

First Published: 7 September 2026

Treated Ruby Inclusions

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

Further evidence is found by carefully examining the mixed crystal exsolved rutile silk. Such inclusions typically unmix into two different solid phases, one highly reflective and the other of lower relief. When such crystals are heated, the lower relief crystals may begin to break down, developing irregular white patches, as one can see here, particularly in the crystal at the center left of the field of view.
Spall marks on the surface of this Mozambique ruby prove that it was heat-treated after cutting and polishing.
Spall marks on the surface of this Mozambique ruby prove that it was heat-treated after cutting and polishing. Note that some of the spall marks have dark halos around them.
A small melted crystal and associated thin film inclusion dazzle with color when lit with fiber optic illumination. Inclusions like these are typical in Thai/Cambodian ruby.
The oiling of gems to improve their appearance is a treatment we see with increasing frequency, particularly with gems originating in Myanmar. Here is a Mogok ruby that shows oil leaking from the fissures following a few minutes contact with the hot point.
Cottony heated diaspore silk in a ruby from Jegdalek, Afghanistan.
A chalky angular pattern, viewed here in shortwave UV illumination, is a strong sign of heat treatment. Many rubies from Mong Hsu, Myanmar, are heated to remove the blue zones that are often present in the natural material.
Careful observation of the surface of the fissure in this ruby reveals a lower luster, providing evidence of glass filling.
Both the cavity and its associated fissures on the edge of this ruby display a lower luster than the surrounding corundum, providing evidence that the stone has been glass filled.
The flattened gas bubbles in this fissure provide evidence that this ruby has been filled with glass.
A glass filled cavity is visible on the surface of this ruby. The rounded indentation is an area where a gas bubble was cut through.
When iron-poor rubies from metamorphic deposits are heat treated, they often develop angular chalky zones when viewed in shortwave ultraviolet light. A great example of this is shown in this photograph, taken with Magilabs Deep Ultraviolet tool.

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Treatment can alter existing inclusions and produce new microscopic features in ruby. These may include changes to mineral inclusions, altered rutile silk, tension fractures, healed fissures, residues and other features associated with heating, fissure healing, glass filling and other treatment processes.

Treated Ruby Inclusion Photomicrographs

The Hyperion treated ruby gallery includes microscopic features documented in natural rubies subjected to treatment. Each entry identifies the recorded treatment and is accompanied by descriptive information and, where available, references to the gemological literature.

What Inclusions Can Reveal About Ruby Treatment

Microscopic examination is an important part of detecting treatment in ruby. The appearance and alteration of inclusions, fractures and growth features can provide evidence of treatment and, in some cases, information about the processes to which a ruby has been subjected.

Hyperion combines inclusion photomicrography with supporting gemological information so that treatment-related features can be compared with documented examples in natural ruby.

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.