0.50 Ct. Yellowish Green Sapphire from Madagascar

This half carat, fancy shaped yellowish green sapphire from Madagascar is a superb example of natural corundum in a compact, wearable size, weighing 0.50 carat and measuring 3.51 by 4.99 by 3.13 millimeters. Cut as a mixed brilliant, the pavilion and crown are faceted to combine the sparkle of a brilliant cut with the broad, reflective planes of step facets, and the excellent polish produces crisp, mirror-like facet surfaces. At eye level the clarity is graded very, very slightly included, meaning that minute inclusions are essentially negligible to unaided vision and do not interrupt the gem’s overall transparency or light performance. The stone displays a light color intensity that reads as a delicate yellow-green, a tone that is both versatile for design and indicative of its natural origin, and notably the gem is untreated, with no enhancement having been applied to modify color or clarity, a factor that significantly adds to its desirability for informed buyers. At The Natural Sapphire Company we document origin and treatment status carefully, and this sapphire’s Madagascar provenance is consistent with the island’s reputation for producing an array of attractive, naturally colored sapphires.

What gives this sapphire its particularly lively sparkle is a combination of intrinsic crystal properties and thoughtful cutting. Corundum, the mineral species of sapphire, has a high refractive index, approximately 1.762 to 1.770, which governs how strongly light is slowed and bent as it enters the gem, producing bright internal reflection. Its relatively low dispersion, about 0.018, means it does not flash spectral fire like diamond, yet the strong refraction yields excellent brightness and contrast. Corundum’s small but measurable birefringence, typically around 0.008, and the potential for pleochroism in colored sapphires contribute to subtle shifts in hue and intensity as the gem is rotated, so a properly faceted mixed brilliant will catch light in multiple ways, alternating between scintillation from the brilliant-cut crown and broad flashes from the step-influenced pavilion. The mixed brilliant design on this fancy shape is calibrated to these optical constants, maximizing return of light to the viewer’s eye while controlling light leakage through precise angles and facet junctions. Because the polish is excellent and the internal inclusions are minimal at the eye level, facet edges read cleanly and reflections remain sharp, producing a scintillation pattern and lively appearance that is disproportionate to the stone’s modest size, a quality that makes this gem feel unusually bright and animated compared with lesser cuts or more heavily included material.

For the educated buyer, value resides not only in color and carat, but in the combination of origin, treatment status, cutting quality, and optical performance, all of which this sapphire embodies. Madagascar is a well-regarded source for natural sapphires with a range of colors, and the absence of heat or diffusion treatments preserves both the stone’s natural character and market premium. The light yellowish green tone is particularly useful for designers seeking a soft but distinct color that complements both warm and cool metals, and at 0.50 carat the gem is ideally sized for a center stone in delicate engagement styles, a halo, or as an accent in bespoke pieces where precise color matching and optical performance matter. From a practical standpoint the hardness of corundum, nine on the Mohs scale, assures long-term durability for daily wear, while its stable color and polish make it straightforward to set in open-backed or partially open settings to allow maximum light entry. When you choose a natural, untreated sapphire like this one from The Natural Sapphire Company you are selecting a gem whose sparkle is a product of natural crystalline structure and human craftsmanship combined, and that combination is what delivers the confidence and enduring beauty experienced by discerning collectors and designers alike.