5.66 Ct. Blue Sapphire from Ceylon (Sri Lanka)

This sapphire is a transparent, cushion shaped natural blue sapphire, weighing 5.66 carats, with precise dimensions of 8.86 by 8.52 by 7.81 millimeters. The gem is fashioned with a mixed brilliant cut that combines a faceted pavilion and a faceted crown to optimize both light return and scintillation. Clarity is graded as very very slightly included, evaluated at eye level, which for practical purposes reads as eye clean and permits clean facet reflections across the table and crown. Color presents as vivid blue, a vibrancy that is characteristic of high quality Ceylon material, and the surface exhibits an excellent polish which enhances both contrast and sparkle. This sapphire is untreated, showing no enhancement, and its documented origin is Ceylon Sri Lanka. The Natural Sapphire Company presents this stone as a natural, unheated example of Ceylonese blue, preserved in its original state for accurate assessment of optical performance and long term durability.

Optically the stone displays a lively interplay between strong facet by facet light return and broad, saturated body color, a combination that distinguishes well cut Ceylon sapphires from many other specimens. The mixed brilliant pavilion and crown create a pattern of pinpoint scintillation combined with broader flashes of blue that move dynamically as the stone or the observer moves, the high transparency amplifying these effects. Sapphire, as corundum, has a vitreous luster and a refractive index near 1.76 which produces bright, glass like reflections rather than the high dispersion fire seen in diamond. Compared to Kashmir sapphires, which are often described as velvety with a softer light scattering due to fine silk inclusions and slightly lower transparency, this Ceylon piece reads as brighter and more lively, with crisper facet reflections and more apparent scintillation. Compared to Burmese sapphires, which can present denser, royal blue saturation and a greater sense of depth, the Ceylon piece offers more immediate brilliance and a lighter, more electric tone. Against Madagascar sapphires and heated material, the untreated Ceylon example retains a natural clarity and color zoning that contributes to dynamic pleochroic shifts, whereas heavily heated or diffusion treated material can exhibit more homogenized color and occasionally reduced scintillation due to internal diffusion effects.

From a practical and design perspective, the combination of vivid Ceylon color, mixed brilliant cut, eye clean clarity, and excellent polish makes this sapphire exceptionally well suited to settings that showcase both color and light performance. In open table settings such as solitaire rings, halo designs with well proportioned surrounds, and pendant mounts that allow downward light entry, the stone will maximize its pinpoints of scintillation and full body color, appearing lively in motion and saturated in static viewing. The stone’s lack of enhancement ensures stable color over time and predictable behavior under different lighting conditions, important considerations for custom fabrication and future resale. For comparative evaluation within the category of premium blue sapphires, this 5.66 carat Ceylon cushion balances the bright, vivacious reflections associated with Sri Lankan material with the transparency and facet crispness that collectors expect from unheated stones, a combination documented and offered by The Natural Sapphire Company for clients seeking clarity of optical character alongside natural provenance.