1.52 Ct. Purplish Blue Sapphire from Tanzania

This gemstone is a transparent 1.52 carat cushion shape purplish blue sapphire, with exact dimensions of 6.48 x 5.60 x 4.48 mm. It has a mixed brilliant cut, a clarity grade slightly included evaluated at eye level, intense color intensity, and an excellent polish. There has been no enhancement to the stone, and it is of Tanzanian origin. The Natural Sapphire Company presents this sapphire with full disclosure of its measured proportions and grading attributes, reflecting the stone as cut and finished rather than described by hypothetical or assumed treatments.

The sapphire derives its exceptional sparkle from a combination of material properties and precise cutting geometry. As a corundum species, sapphire has a relatively high refractive index of approximately 1.76 to 1.77, which governs the degree to which light is bent and contained within the crystal. When light enters the stone it is refracted at the crown, reflected across the pavilion facets, and returned to the observer as both steady white brilliance and dynamic scintillation. The mixed brilliant cut employed here pairs a faceted crown with a more complex pavilion geometry, an approach that optimizes both light return and sparkle for the cushion outline. The brilliant facet pattern on the crown creates numerous small face up reflections that generate lively scintillation as the stone or the wearer moves, while the pavilion facets guide and concentrate light back through the crown to produce consistent brightness. Careful proportioning of table size, crown height, and pavilion depth ensures that light is neither lost through leakage nor trapped inefficiently, resulting in an overall light performance that is markedly lively for a colored stone.

Beyond the cut, the stone’s internal clarity and color contribute directly to the quality of its sparkle. The sapphire is transparent and evaluated as slightly included at eye level, meaning inclusions are present but do not significantly interrupt the passage of light through the gem nor the continuity of facet reflections when viewed face up. This degree of clarity allows the stone to maintain strong internal reflections, while the intense purplish blue saturation supplies chromatic depth that enhances perceived brightness and contrast. Because corundum has relatively low dispersion, the rainbow like fire seen in gem materials with high dispersion is not the primary contributor to this sapphire’s visual appeal. Instead, the combination of high refractive index, responsive facet geometry, and saturated hue produces a silvery white brilliance intertwined with deep color flashes, which creates a compelling sense of depth and life that is frequently described as scintillation driven rather than fire driven.

The finishing details further elevate the stone’s light performance. An excellent polish produces crisp, mirror like facet surfaces and well defined facet junctions, minimizing surface scattering and preserving the purity of internal reflections. The cushion outline, with its softened corners and balanced table, delivers a distinct blend of classic form and contemporary sparkle, and the mixed brilliant cut maximizes the interaction between the stone and ambient light. Because no enhancement has been applied, the stone’s color and optical response are the result of natural formation and cutting skill, without the influence of treatments that can alter light behavior. The Tanzanian origin is documented, and The Natural Sapphire Company stands behind the gem’s description and condition, providing provenance and measured specifications to assist in evaluation and setting decisions. The combined effects of material properties, exacting facet design, and superior finishing result in a sapphire whose sparkle is structurally driven, precise, and consistent under varied lighting conditions.