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.
A melted crystal with a frozen gas bubble inside is suspended over a backdrop of partially dissolved silk which displays “inkspot” internal diffusion.
Natural Sapphire •
Thailand (Siam); Bo Ploi •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Oblique
Photographer:
E. Billie Hughes •
Image Number:
A-002-3182-1
Tiny melted crystals and heat-altered fingerprints suggest that this sapphire has undergone heat treatment.
Natural Sapphire •
Madagascar •
Enhancements:
Heat (H) •
Lighting Conditions:
Dark Field + Diffuse Fiber Optic
Photographer:
E. Billie Hughes •
Image Number:
A-002-2565-1
“Ink spot internal diffusion” surrounding partially resorbed rutile silk indicates that this stone has been heated. During treatment, the rutile dissolves, sending titanium into solution, thus coloring the stone blue around the silk.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Diffuse Light Field (Transmitted Light)
Photographer:
Patharaphum Sudprasert •
Image Number:
A-002-1566-1
Koivula, J.I. (1987) Internal diffusion. Journal of Gemmology, Vol. 20, No. 7/8, pp. 474–477; RWHL*.
A glassy discoid around this mica crystals suggests that its pink sapphire host was heat treated.
Natural Sapphire •
Madagascar •
Enhancements:
Heat (H) •
Lighting Conditions:
Dark Field + Diffuse Fiber Optic
Photographer:
E. Billie Hughes •
Image Number:
A-002-1531-1
Triangular growth zoning in a Madagascar sapphire. Milky regions contrasting with deep blue zones are common in Madagascar sapphire.
Natural Sapphire •
Madagascar •
Enhancements:
Heat (H) •
Lighting Conditions:
Dark Field + Oblique Fiber Optic
Photographer:
Patharaphum Sudprasert •
Image Number:
A-001-9419-1
Melted crystals surrounded by heat-altered fingerprints in a heat-treated Madagascar sapphire.
Natural Sapphire •
Madagascar •
Enhancements:
Heat (H) •
Lighting Conditions:
Diffuse Light Field + Fiber Optic
Photographer:
Patharaphum Sudprasert •
Image Number:
A-001-8832-1
Hughes, R.W. (1997) Ruby & Sapphire. Boulder, CO, RWH Publishing, 512 pp.; RWHL*.
Red-orange crystals shoot through this Pailin (Cambodia) sapphire. Once considered unique to Pailin sapphire, we now know that such uranopyrochlore inclusions are found in sapphires from many sources.
Natural Sapphire •
Cambodia; Pailin •
Enhancements:
Heat (H) •
Lighting Conditions:
Dark Field + Oblique Fiber Optic
Photographer:
E. Billie Hughes •
Image Number:
A-001-8453-2
These melted snowball crystals with glassy discoids provide evidence of heat treatment in this Sri Lanka sapphire.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Diffuse Oblique
Photographer:
E. Billie Hughes •
Image Number:
A-001-7683-2
These melted snowball crystals with glassy discoids provide evidence of heat treatment in this Sri Lanka sapphire.
Natural Sapphire •
Sri Lanka (Ceylon) •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Diffuse Oblique
Photographer:
E. Billie Hughes •
Image Number:
A-001-7683-1
A frozen gas bubble shines in a negative crystal in this heated basaltic sapphire. When illuminated from some angles, there is a visible fissure surrounding the crystal, providing further evidence of heat treatment.
Natural Sapphire •
Nigeria •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Diffuse Oblique
Photographer:
E. Billie Hughes •
Image Number:
A-001-7505-6
A frozen gas bubble shines in a negative crystal in this heated basaltic sapphire.
Natural Sapphire •
Nigeria •
Enhancements:
Heat (H) •
Lighting Conditions:
Fiber Optic: Transmitted
Photographer:
E. Billie Hughes •
Image Number:
A-001-7505-5
Frozen gas bubble in a melted negative crystal in basaltic sapphire.
Natural Sapphire •
Nigeria •
Enhancements:
Heat (H) •
Lighting Conditions:
Diffuse Light Field (Transmitted Light)
Photographer:
Patharaphum Sudprasert •
Image Number:
A-001-6887-1
Search the Complete Hyperion Database
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.
