1.68 Ct. Blue Sapphire from Ceylon (Sri Lanka)

This specimen is a transparent blue sapphire, weighing 1.68 carats, cut in an asscher octagon outline, with precise dimensions of 6.72 by 6.68 by 3.88 millimeters. The cutting style is fully faceted in the classic asscher format, presenting concentric step facets on the crown and pavilion that converge to a broad table. The stone is evaluated as eye clean at normal viewing distances, with an intense color intensity that reads as vivid blue without visible zoning. The polish has been executed to an excellent standard, creating crisp facet junctions and smoothly finished facet planes. The sapphire has undergone standard heat treatment to enhance saturation and clarity, a stable and widely accepted practice in the trade. The material is from Ceylon Sri Lanka, an origin noted for lively, vibrant blue tones, and it is offered through The Natural Sapphire Company.

The asscher architecture employed here emphasizes proportional symmetry and controlled light movement. The near perfect square proportions with octagon shoulders yield a face up outline that is 6.72 by 6.68 millimeters, delivering a depth of 3.88 millimeters which corresponds to a depth of approximately 57.9 percent of the average face dimension. This proportion sits in an optimal range for step cut sapphires, balancing face up color saturation with effective light return. Step facets on the crown are broader and fewer in number than brilliant facets, producing larger, broad flashes of reflected light rather than the many small scintillating points seen in brilliant cuts. The excellent polish minimizes light scattering at facet junctions, enhancing contrast between bright step flashes and dark hall of mirrors planes, and the controlled pavilion angles support strong internal reflection while limiting windowing where light passes through without meaningful return.

Optically this Ceylon asscher sapphire behaves in ways characteristic of corundum, and its reflective qualities differ markedly from other stones in its peer group. Corundum has a refractive index in the range of approximately 1.760 to 1.770 and a low birefringence in the range of approximately 0.008 to 0.010, attributes that yield high brilliance with limited double image effects. Compared to brilliant cut sapphires which use numerous small facets to create extensive scintillation, the asscher step cut produces architectural broad flashes and a mirror like interplay that emphasizes clarity and body color. Against emerald cut sapphires the asscher typically reads slightly brighter face up because of its more compact table and stepped crown geometry, which concentrate reflections centrally. Against other blue gemstones commonly compared to sapphire, such as spinel with a refractive index around 1.718, tanzanite with an index near 1.691 to 1.700, and aquamarine with an index near 1.577 to 1.583, this sapphire will typically present stronger contrast and crisper facet reflections due to its relatively higher refractive index and greater specific gravity near 3.95 to 4.03. Compared to diamond this sapphire will show far less dispersion or fire, because diamond has a much higher refractive index and much higher dispersion, however the sapphire offers a saturated body color and a depth of tone that diamonds inherently lack. The asscher cut further reduces perceptible pleochroic shifts by presenting large flat facets that integrate color across broader face up areas, an advantage for viewing uniformity in a material that can display dichroism along different crystallographic axes.

From a craftsmanship and setting standpoint this 1.68 carat asscher blue sapphire is particularly well suited to jewelry where clean, architectural aesthetics are desired. The eye clean clarity grade allows the asscher step pattern to read without interruption from included silk or crystal intersections, letting the intense Ceylon blue present uniformly across the table. Heat treatment, disclosed, has stabilized the blue saturation and is consistent with long term color stability under routine wear conditions. For practical design advice, settings that allow ample light to reach the pavilion, such as moderate open prong baskets or low profile bezel variants with an open gallery, will optimize the visible brightness and reinforce the hall of mirrors effect. Metal choice will affect perceived color, with platinum and white gold tending to accentuate cooler blue notes, and warm gold alloys subtly enriching the perceived depth. Given corundum hardness of nine on the Mohs scale, this sapphire provides excellent durability for daily wear. At The Natural Sapphire Company we present this asscher octagon as a technical and aesthetic choice for connoisseurs who value facet architecture, precise proportions, and the living interplay of light and color that a well cut Ceylon sapphire can deliver.