1.01 Ct. Bi Color / Parti Sapphire from Ceylon (Sri Lanka)

This 1.01 carat round, bi color or parti sapphire from Ceylon Sri Lanka, offered by The Natural Sapphire Company, is a study in optical precision and gemological quality. The stone measures 5.94 x 6.02 x 3.89 mm and is faceted in a mixed brilliant cut that combines a brilliant crown with a carefully proportioned pavilion. The clarity grade is very very slightly included when evaluated at eye level, ensuring that light travels through the gem with minimal interruption. Color intensity is vivid and the polish is excellent, attributes that work together with the cut to deliver lively scintillation and a strong visual presence for a one carat stone. This sapphire has been heat treated, a standard and stable enhancement that improves color saturation and overall transparency while respecting the gemological integrity expected by informed buyers.

From a structural and optical perspective this sapphire demonstrates why corundum is prized for brilliance and durability. Corundum is aluminum oxide with a trigonal crystal structure, a refractive index in the range of 1.762 to 1.770, a birefringence of approximately 0.008, and a dispersion of about 0.018. Those physical parameters mean that a well cut sapphire returns light efficiently with pronounced brilliance and scintillation, even though its fire is subtler than that of higher dispersion gemstones. The mixed brilliant cutting style here is specifically chosen to harness corundum physics, aligning crown facet angles to maximize internal reflection and using a slightly deeper pavilion, approximately 65 percent of the average diameter, to enhance color saturation and ensure strong face up color. The very very slightly included clarity grade indicates that inclusions are minimal at eye level and will not disrupt the light paths that create sparkle, while the excellent polish preserves crisp facet junctions that contribute to lively facet contrast.

For the educated buyer this sapphire represents a balanced combination of provenance, optical performance, and practical durability. The Ceylon origin imparts a pedigree associated with finely colored sapphires and parti zoning, heat treatment is disclosed and consistent with market practice, and the measured proportions and superior polish deliver repeatable brilliance in settings that demand both color and light performance. Whether set as a solitary center or incorporated into a bespoke design, this gemstone is an asset that reflects both aesthetic appeal and sound gemological attributes, backed by the expertise of The Natural Sapphire Company.