0.70 Ct. Blue Sapphire from Ceylon (Sri Lanka)

This listing describes a transparent, natural Ceylon blue sapphire supplied by The Natural Sapphire Company. The gem weighs 0.70 carat, is fashioned in an oval outline, and measures approximately 6.48 by 4.71 by 2.68 millimeters. The pavilion and crown have been cut to a mixed brilliant style, combining a faceted crown layout with a modified pavilion to balance brilliance and face up size. Clarity is graded as slightly included when evaluated at eye level, which permits strong transparency while maintaining natural internal characteristics. Color presents as medium intensity blue, a hue typical of Ceylon origin yet with a lighter, more lively tone than darker, highly saturated stones. The surface finish is excellent, with precise facet junctions and polish that support crisp light return. Importantly, this sapphire is unenhanced, remaining in its natural state without heat treatment or other modifications, a factor that often appeals to collectors and those seeking untreated provenance.

Optical performance reflects the inherent properties of corundum, which yields a bright, white luster and robust light return when well cut and polished. The mixed brilliant cut on this oval sapphire emphasizes scintillation across the table and shoulders, producing an even pattern of flashes as the stone moves. Because corundum has a relatively high refractive index, this sapphire displays more brilliance and apparent depth than gemstones with lower refractive indices. Compared to other blue gems commonly considered as alternatives, such as aquamarine and blue topaz, this sapphire exhibits stronger contrast between light and dark facets and a firmer, more immediate return of light. Against tanzanite and certain spinels, which can show strong pleochroism or slightly softer luster, the sapphire maintains a steady, lively brilliance rather than color shifting. When compared to other sapphires within the corundum family, the reflective character of this Ceylon stone leans toward a blend of sparkle and windowing resistance, producing lively surface reflections while preserving a clear, open window to the color. The slightly included clarity contributes subtle internal reflections that can enhance visual texture without significantly impeding brightness, and the excellent polish ensures facet planes act as clean mirrors for incident light.

From a practical perspective this sapphire is well suited to settings that capitalize on its clarity, cut, and color, including solitaire rings where the mixed brilliant faceting can maximize face up scintillation, and pendants where the stone can be presented to available light for best effect. The medium color intensity gives versatility in metal choice and mounting style, allowing the gem to read as vivid without overwhelming delicate designs. Because the stone is unheated and of Ceylon origin, it carries attributes that are often sought for authenticity and natural character, while the slightly included clarity provides a record of natural formation rather than detracting from visual appeal. Care recommendations follow standard practices for corundum, including avoiding sudden temperature extremes and keeping abrasive contact to a minimum, which will help preserve the excellent polish and long term reflective performance. The Natural Sapphire Company provides detailed documentation and imagery to support the gem description, and further technical information can be supplied on request for those who require full provenance and grading detail.