4.24 Ct. Blue Sapphire from Ceylon (Sri Lanka)

From the riverbeds of Ceylon in Sri Lanka this sapphire began its journey as a fragment of the islands ancient geology, carried and concentrated by water and time until miners with generations of local knowledge recovered it. At The Natural Sapphire Company we honored that origin, and sent this clean, transparent 4.24 carat oval blue sapphire to the hands of our most skilled cutters. Measuring 11.73 x 8.99 x 5.05 mm this gem has been fashioned into a mixed brilliant cut that balances a faceted pavilion with a brilliant crown to maximize life and motion. Its medium color intensity captures the classic Ceylon blue, and its clarity grade of slightly included evaluated at eye level is a testament to its natural character and authenticity. The stone has been heat treated in a manner customary for Ceylon sapphires to refine color and clarity, and an excellent polish brings its surface to a mirror finish that invites the eye to linger.

The sapphire owes its exceptional sparkle to the very nature of corundum and to the thoughtful marriage of cut and polish. As aluminum oxide with trace titanium and iron, its crystal lattice produces a high refractive index and a subtle uniaxial birefringence, which together bend and split light within the stone in ways that create depth and scintillation unique to sapphire. The mixed brilliant cut amplifies this behavior by opening the crown to catch light and by angling the pavilion facets to return that light to the viewer, creating flashes of lively brilliance across the oval face. Because corundum rates nine on the Mohs scale the facets remain crisp and the excellent polish endures, so the contrast between dark and light facets is maintained and the sparkle remains pronounced. Slight inclusions offer internal textures that act like tiny mirrors at certain angles, adding character without diminishing the overall transparency. This versatile 4.24 carat oval will command a centerpiece setting and will reflect day and evening light with a cool, ocean blue fire. At The Natural Sapphire Company we invite you to experience this gem in person and to imagine it set into a design that will celebrate both its Ceylon story and its structural brilliance.