1.68 Ct. Blue Sapphire from Ceylon (Sri Lanka)

This round blue sapphire weighs 1.68 carat, and measures 7.12 x 7.13 x 4.11 mm, presenting a near ideal table to diameter relationship for face up appearance. The gem was fashioned in a mixed brilliant cut, combining a faceted brilliant crown with a precision modified pavilion, a configuration that enhances both chroma saturation and controlled brilliance. With a measured depth of 4.11 mm against an average girdle diameter of 7.125 mm, the depth sits at approximately 57.7 percent, a proportion that balances light return with preservation of natural rough weight. Facet geometry shows crisp junctions and well defined facet planes, consistent with the reported excellent polish. At the material level this sapphire is corundum, with the intrinsic refractive index and dispersion characteristics that produce strong color saturation and resilient optical performance, and a hardness of 9 on the Mohs scale that ensures long term durability in everyday wear.

Color is the defining attribute of this stone, graded as intense in color intensity, with a richly saturated primary blue that reads richly vivid under standard daylight viewing conditions. The mixed brilliant architecture concentrates blue saturation in the face up window, yielding a uniform visual field with lively internal flashes from the crown facets. The sapphire evaluates as eye clean when examined at normal viewing distance, meaning no inclusions are visible to the unaided eye, which preserves the stone clarity and allows uninterrupted color depth. The stone has been heat treated, a stable and widely accepted enhancement practice in which thermal processing refines tone and reduces microscopic silk without compromising structural integrity. Heat treatment is disclosed, and the resulting optical gains in saturation and transparency are evident, while the excellent polish ensures minimal light leakage at facet junctions and strong scintillation across varied lighting environments.

The origin of this sapphire is Ceylon, Sri Lanka, a historical source known for producing stones with a lively, vivid blue that often exhibits a slightly lighter, more electric character relative to deeper basaltic sources. At The Natural Sapphire Company we emphasize provenance and traceability, maintaining direct relationships with trusted partners in Sri Lanka and employing documented supply chain practices. Each stone is sourced with attention to responsible mining methods, fair labor practices, and transparent chain of custody, and we support independent verification of origin where permissible. For the conscious consumer these factors are integrated into the valuation, as ethical sourcing reduces non material risk and aligns acquisitions with sustainable standards. Our team documents the stone history from rough purchase through cutting and finishing, and we make those records available to clients seeking confirmation of ethical sourcing.

For collectors and designers the 1.68 carat round mixed brilliant sapphire is versatile, ideal for a solitary engagement setting that maximizes the face up blue, or as a central element in a halo design that leverages the stone color against complementary accent diamonds. The gem sets particularly well in settings that allow light to enter through the pavilion, such as four or six prong mounts, which emphasize the mixed brilliant cut dynamics and maintain the stone face up saturation. Care is straightforward, using warm soapy water and a soft brush for routine cleaning, and avoiding sudden thermal shocks or harsh abrasives that could stress the mounting. We provide independent certification and full disclosure of the heat treatment, and our gem specialists at The Natural Sapphire Company can supply additional documentation, magnified imagery, and recommended mounting specifications. For the ethically minded buyer who values technical precision, transparent sourcing, and enduring beauty, this Ceylon sapphire represents a considered addition to a curated collection.