Spinel Inclusions

First Published: 7 September 2026

Spinel Inclusions

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

Apatite is a common inclusion in spinel. Here we can see it in both a more rounded and elongated form. The identity of the apatite was confirmed with Raman spectroscopy. Specimen courtesy Ayub Muhammad.
This small inclusion was partially cut through on the surface. It turned out to be phlogopite mica (tested via micro Raman). To the best of our knowledge, this is the first time phlogopite has been reported in Mahenge spinel.
This small inclusion was partially cut through on the surface. It turned out to be phlogopite mica (tested via micro Raman). To the best of our knowledge, this is the first time phlogopite has been reported in Mahenge spinel.
Liquid fingerprints in spinel are rather uncommon. Here we see a rare example, more highly magnified.
Liquid fingerprints in spinel are rather uncommon. Here we see a rare example.
This healed fissure in a cobalt-bearing color-change spinel shows tiny negative crystals in the plane of the former fissure.
This cobalt blue spinel shines with a green fluorescence when viewed in longwave ultraviolet illumination.
Spinel fingerprint in a red spinel. These consist of tiny octahedron-shaped negative crystals in a fingerprint pattern.
Iridescence on multiple planes of unknown composition in a cobalt blue spinel.
When we saw the criss-crossing twin planes in this crystal inclusion inside a spinel, we thought that it is likely a calcite crystal. This suspicion was confirmed with raman microscopy.
A small tube-like cavity pierces the surface of this cobalt spinel.
When we saw several metallic crystals in the interior of this spinel we became curious as to their identity. Micro Raman analysis revealed that they are graphite.

Search the Complete Hyperion Database

Spinel inclusions may include mineral crystals, healed fissures, fluid inclusions, negative crystals, growth features and other internal features formed during or after crystal growth. Such features are important to gemologists because they can provide evidence useful in identifying spinel, understanding its geological history, recognizing treatment and, in some cases, determining geographic origin.

Spinel Inclusion Photomicrographs

The Hyperion spinel gallery includes microscopic features found in spinels 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 Spinel

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

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