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.

Transparent, doubly refractive crystals in a spinel from Vietnam.
A network of coarse negative crystals forms in a fingerprint pattern in this spinel from Myanmar’s Mogok Stone Tract.
Doubly refractive crystals light up with colorful interference colors when viewed between crossed polars in this dark blue spinel from Ceylon.
A fingerprint inclusion in a natural spinel from Vietnam, Luc Yen mines. The individual channels of a fingerprint are actually tiny negative crystals.
Growth zoning pattern in a Burma spinel.
Stellate dislocations decorate the interior of this spinel from Vietnam’s Luc Yen district. These may sometimes alter to hogbomite.
This frosty-looking melted crystal provides evidence that it’s Tanzanian spinel host was heat treated.
Decrepitation halo around a heat-altered crystal in a heated Mahenge spinel.
This birefringent crystal lights up under crossed polars in its host, a cobalt blue Sri Lankan spinel.
This “belly button” apatite crystal is a classic inclusion in spinel. The black belly button is a crystal of either ilmenite or graphite on the surface of the rounded apatite crystal. These are common features of spinels from both Myanmar and Sri Lanka.
A prominent, intricate fingerprint pattern consisting of interconnected communication tubes extending from a mineral inclusion nucleus serves to confirm that this Sri Lankan spinel is natural. The form taken by the tubes reveals the isometric symmetry of the underlying spinel. 5X
This spinel from Madagascar displayed a number of these inclusions, which consisted of a solid crystal surrounded by a cloud of tiny inclusion.

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.

Search the Complete Hyperion Database