15.29 Ct. Ametrine from Madagascar

This gem is a transparent 15.29 carat oval shaped bi color ametrine with precise dimensions of 17.63 x 13.92 x 9.52 mm, executed in a mixed brilliant cut to maximize both scintillation and color presentation. The cutter has retained a classic oval outline with a length to width ratio of approximately 1.27, yielding a balanced face up presence that favors even color distribution across the table. Clarity is described as very slightly included when evaluated at eye level, and the stone exhibits a medium light color intensity with excellent polish. Heat treatment has been applied to stabilize and enhance the purple and golden yellow zones, a common and accepted enhancement in ametrine processing, carried out to refine tone depth without compromising the transparency or structural integrity of the crystal. The overall result is a clean, lively gemstone with vivid bi color contrast and a refined surface finish, offered by The Natural Gemstone Company.

The mixed brilliant faceting is designed with a brilliant crown to produce strong pinfire and larger scintillation, combined with a more subtle pavilion arrangement that controls light leakage and enhances return through the table. The cutter used a tight, well proportioned crown profile to maintain face up brilliance, while the pavilion facets were calibrated to prevent windowing and promote uniform light return across the bi color boundary. The facet junctions are crisp, and the excellent polish allows for unobstructed internal reflections that emphasize both hues. In oval form, careful attention to girdle thickness and symmetry is essential, and this specimen shows consistent facet alignment from crown to pavilion, minimizing extinction and producing a stable, pleasing pattern of light. The mixed brilliant style also assists in blending the purple and yellow sectors at different viewing angles, providing an attractive sparkle that complements the bi color character.

From a clarity and inclusion standpoint the stone conforms to a very slightly included appearance at typical viewing distance, with minute natural features that do not distract from the gem while providing internal fingerprinting unique to this crystal. These inclusions are small and well located, not intersecting critical facet junctions or the girdle, and they do not introduce durability concerns for routine jewelry settings. The medium light color intensity has been balanced by the cutter to avoid overly dark zones that can mask the yellow or purple, and to preserve attractive contrast when set in rings or pendants. The bi color zoning in this ametrine is pronounced yet harmonious, with a soft transition at the color interface that allows varied presentation depending on light source and viewing angle. For lapidary informed buyers, the stone will demonstrate consistent pleochroic tendencies typical of ametrine related materials, and orientation in a final setting can be used to favor either the purple or yellow face up, depending on design intent.

The origin of this ametrine is Madagascar, and this provenance contributes materially to its desirability and market value. Madagascar produces high quality gem crystals in distinct geological contexts, and ametrine material from this region often exhibits larger crystal sizes and unique color zoning patterns not commonly found in the classic Bolivian sources. Provenance from Madagascar also allows informed buyers to assess geological narrative and supply chain considerations, and at The Natural Gemstone Company we document origin to support both aesthetic and investment assessments. The application of heat treatment in a controlled manner is fully disclosed, and this processed enhancement is consistent with best practices for stabilizing and optimizing color in natural ametrine. For collectors and designers seeking a substantial oval ametrine with technical refinement, this 15.29 carat example offers an exceptional combination of size, cut quality, clean clarity, and provenance, making it a compelling choice for bespoke jewelry or a focused gemstone collection.