1.60 Ct. Color Change Sapphire from Ceylon (Sri Lanka)

This 1.60 carat oval Color Change sapphire from Ceylon Sri Lanka represents a confluence of precision cutting, unaltered natural origin, and an internal fingerprint that is unmistakably characteristic of fine Ceylon material. The gem measures 7.59 x 5.89 x 4.18 mm, producing a depth to mean dimension ratio of approximately 62.1 percent, a proportion that balances color saturation with optimal light return in an oval outline. Cut as a mixed brilliant, the crown employs a modified brilliant facet arrangement to maximize scintillation and fire, while the pavilion transitions to a more controlled facet architecture that preserves color depth and directional color shift. The combination of a lively brilliant crown and a pavilion that supports color retention is a deliberate choice made to enhance the color change phenomenon, and the excellent polish and careful symmetry ensure that light interacts consistently across the girdle, producing a stable and predictable visual response under different illuminants.

Clarity evaluation at eye level is eye clean, allowing the stone to present its vivid color intensity without visible disturbance from the surface or internal features during normal wear. Under magnification the inclusion suite reveals the signature markers that distinguish this sapphire and confirm its provenance and treatment history. Fine oriented needle silk is present, aligned along crystallographic planes, forming delicate networks and occasional dense planes that diffuse light and contribute to the stone velvet at certain angles. These silk planes remain intact and well defined, a strong indicator of absence of heat enhancement, as thermal treatment typically alters or dissolves rutile silk. In addition there are isolated mineral crystal inclusions with strong relief against the host corundum, tiny negative crystal cavities and healed feather like growth features that follow growth zoning patterns. The growth zoning itself is apparent as angular and sectorial bands of color and transparency, an internal map that reflects natural growth conditions in Ceylon pegmatitic and metamorphic environments.

These inclusions are not flaws to be hidden, they are the signature that makes this sapphire unique. The oriented silk contributes to a nuanced scattering of light that accentuates the cool to warm shift in hue, scattering shorter wavelengths in daylight and allowing warmer wavelengths to dominate under incandescent illumination. The isolated mineral crystals act as micro mirrors that introduce pinpoint flashes, and the healed feathers and fingerprints create soft halos that modulate saturation locally, producing a living surface to the color that changes with viewing angle and light source. Combined with pronounced pleochroism inherent to corundum, these internal features create a multi modality color behavior where the gem can read differently along its principal optical axes. This is the type of microstructure that sophisticated buyers seek, because it provides verifiable evidence of natural formation and of being unenhanced, while also producing visually complex color change effects that look alive and natural.

Presented and certified by The Natural Sapphire Company as Other certified Color Change material, this sapphire is offered in its natural, untreated state, which is increasingly prized by connoisseurs who prefer the integrity of original crystal growth characteristics. The mixed brilliant faceting strategy, the careful proportioning at 7.59 x 5.89 x 4.18 mm, the eye clean clarity, the vivid color intensity and the excellent polish all work in concert to make the color change clearly visible under differing light conditions while maintaining luxury quality for jewelry settings. Whether set in a halo that further enhances perceived size and color, or in a solitaire that exposes the full range of pleochroic and color changing behavior, this 1.60 carat Ceylon sapphire offers a rare combination of scientific interest and wearable beauty, an unmistakable signature piece for collectors and designers alike.