Heated Sapphire Inclusions
Explore inclusions in heat-treated sapphire in Hyperion, the Lotus Gemology inclusion database. Hyperion contains photomicrographs of inclusions and internal features in natural sapphires that have been subjected to heat treatment, documented with information on geographic origin, lighting conditions, field of view, photographer and published references.
Heat-altered fingerprint in a Sri Lanka blue sapphire. Heating causes tiny microfractures as the negative crystals burst.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Transmitted
Photographer:
Richard W. Hughes •
Image Number:
A-001-2135-1
Small heat-altered feathers just beneath the surface of a heat-treated Sri Lanka sapphire.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Transmitted
Photographer:
Richard W. Hughes •
Image Number:
A-001-2132-1
Yellow color zones in a heat-treated blue sapphire from Sri Lanka fluoresce red when illuminated with a fiber-optic light source.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Oblique
Photographer:
Richard W. Hughes •
Image Number:
A-001-2059-1
Crystals of what are probably apatite in a heated bi-color sapphire from Sri Lanka.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Oblique
Photographer:
Wimon Manorotkul •
Image Number:
A-010-0150-1
Hughes, R.W. (1997) Ruby & Sapphire. Boulder, CO, RWH Publishing, 512 pp.; RWHL*.
Broken hearted. A melted crystal and melted fingerprint decorate the interior of this heat-treated sapphire from Serendib.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Oblique
Photographer:
E. Billie Hughes •
Image Number:
A-001-1892-1
This string of discoids demonstrate that this Sri Lankan sapphire has been subjected to heat treatment.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Oblique
Photographer:
E. Billie Hughes •
Image Number:
A-001-1884-1
Heat treatment has altered these included crystals into white “snowballs.”
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Oblique
Photographer:
E. Billie Hughes •
Image Number:
A-001-1887-1
A heat-induced discoid in a heat-treated sapphire from Serendib.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Oblique
Photographer:
E. Billie Hughes •
Image Number:
A-001-1889-2
A heat-induced discoid in a heat-treated sapphire from Serendib.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Transmitted
Photographer:
E. Billie Hughes •
Image Number:
A-001-1889-1
Indicted and convicted. This melted crystal, fingerprint, and string of melted crystals are positive proof of heat treatment.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Oblique
Photographer:
E. Billie Hughes •
Image Number:
A-001-1891-1
Chalky blue shortwave ultraviolet fluorescence in a heat-treated sapphire from Sri Lanka. Such chalky blue-to-green fluorescence is a strong indicator of heat treatment.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Ultraviolet: Shortwave
Photographer:
Richard W. Hughes •
Image Number:
A-001-1894-1
The Blue Man. Internal diffusion creates a fanciful pattern within this heat-treated sapphire from the Isle of Gems.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Oblique
Photographer:
Richard W. Hughes •
Image Number:
A-001-1888-1
Koivula, J.I. (1987) Internal diffusion. Journal of Gemmology, Vol. 20, No. 7/8, pp. 474–477; RWHL*.
Heat treatment can alter inclusions and other internal features in sapphire. Changes may include modification or dissolution of rutile silk, alteration of mineral crystals, decrepitation of fluid inclusions, changes to healed fissures and the formation of heat-related features. Such evidence can be important in determining whether a sapphire has been heated.
Heated Sapphire Inclusion Photomicrographs
The Hyperion heated sapphire gallery includes microscopic features documented in heat-treated natural sapphires. Each entry is accompanied by descriptive information and, where available, references to the gemological literature.
What Inclusions Can Reveal About Heat Treatment
Microscopic examination is an important part of detecting heat treatment in sapphire. The condition of mineral inclusions, rutile silk, fissures and other internal features can provide evidence of exposure to elevated temperatures. These features are evaluated together with other gemological observations when determining treatment status.
Hyperion combines inclusion photomicrography with supporting gemological information so that heat-related features can be compared with documented examples in treated sapphires.
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.
