4.03 Ct. Blue Sapphire from Ceylon (Sri Lanka)

This exceptionally transparent 4.03 carat cushion shape blue sapphire from The Natural Sapphire Company presents a rare combination of weight, proportion, and vivid color intensity that experienced buyers will immediately appreciate. Measuring 9.91 by 8.68 by 5.70 millimeters, the gem has been fashioned in a mixed brilliant cut that balances scintillation with rich, even face up color. The clarity grade is eye clean as evaluated at eye level, meaning there are no inclusions visible to the naked eye under normal viewing conditions, which significantly enhances the stone’s commercial and aesthetic appeal. The polish is excellent, providing crisp facet junctions and an inviting surface that maximizes light return. The stone has been heat treated, a widely accepted and transparent enhancement that improves tone and saturation, and its origin is Ceylon, Sri Lanka, a source renowned for producing sapphires with lively, velvety blues and fine crystallographic character.

The mixed brilliant cut and cushion outline are central to this sapphire’s optical performance, and they explain much of the gem’s visual allure. The pavilion is faceted to a pattern that promotes strong light return and a lively play of blue flashes, while the crown faceting reduces windowing and deepens the perceived color in varied lighting. The cushion silhouette brings a classic, slightly softened profile on the finger, and at just under 10 millimeters in length the gem has a commanding presence without overwhelming a typical mounting. The relatively moderate depth of 5.70 millimeters has been carefully managed to avoid excessive darkening, preserving brilliance and face up saturation, and the excellent polish ensures that light glides across the gem with minimal surface diffusion. For the discerning buyer who values both technical cutting philosophy and visual impact, these proportions speak to a stone cut with intent to harmonize weight retention with superior performance.

Although the gem is eye clean, under magnification this Ceylon sapphire reveals a suite of natural inclusions that serve as its unmistakable signature, and that experienced gemologists and collectors value as evidence of natural origin and provenance. Typical features include very fine, silk like needle rutile inclusions arranged in subtle patterns, minute mineral crystals localized in growth channels, and delicate healed fingerprints that trace the stone’s internal growth history. In many Sri Lankan sapphires the silk needles scatter light to create a soft, velvety texture to the blue, and in this specimen the interaction between those fine inclusions and the mixed brilliant faceting produces a depth and internal scintillation that reads as both lively and deep. Heat treatment in reputable practice can partially modify or dissolve some rutile silk, improving clarity and intensifying blue saturation, while leaving other microscopic features intact. Those remaining features, including tiny crystals and growth zoning, act like a microscopic landscape, uniquely identifying this sapphire to gemological examination without affecting its beautiful, clean face up appearance.

For an educated buyer the value of this sapphire is clear, and it rests on a confluence of objective factors. The weight at 4.03 carats places the gem in a category where per carat values increase markedly, especially when combined with an eye clean clarity grade and vivid color intensity. The Ceylon origin carries a premium among connoisseurs because Sri Lankan mines are known to produce saturated, velvety blues with distinct internal characteristics that respond well to careful cutting. Heat treatment is fully disclosed, standardized, and in this example applied to optimize color and clarity without compromising the stone’s structural integrity. The mixed brilliant cut and excellent polish translate to practical advantages when set, promising lively scintillation under varied lighting, efficient light return in ring mountings, and an even appearance in both pendant and ring applications. At The Natural Sapphire Company we recommend settings that both protect the girdle and allow light access from the pavilion, such as four or six prong designs with a lower profile bezel option for everyday wear, and we can provide optional gemological documentation on request to support provenance and enhancement disclosure. This sapphire is therefore an investment in both beauty and verifiable gemological quality, ideal for bespoke commissions or for the collector seeking a classic, yet character rich blue sapphire.