8.49 Ct. Ametrine from Madagascar

The Natural Gemstone Company is pleased to present one beautiful transparent 8.49 carat emerald cut bi color ametrine, measuring 15.64 by 12.60 by 6.20 mm. This stone displays a classic emerald cut with crisp step facets and a broad table that emphasizes color zoning and depth of tone. The clarity has been evaluated as very very slightly included at eye level, which means that the inclusions are extremely minor and do not detract from the visual impact when worn or set. The color intensity is rated as medium intense, and the piece benefits from an excellent polish that produces clean facet junctions and mirror like facet faces. The gem has been heat treated, a stable and common enhancement for ametrine that refines the citrine yellow zones and balances the purple amethyst zones without introducing instability. Origin is Madagascar, a source increasingly recognized for producing large, clean crystals with attractive bicolor zoning.

Understanding why this ametrine's sparkle is distinguished begins with the nature of quartz and the way the emerald cut interacts with its internal structure. Ametrine is a naturally occurring bicolor variety of quartz that forms as silicon dioxide in a trigonal crystal system, and its bicolor effect arises from differential oxidation states of iron in adjacent growth zones during crystallization. The refractive index of quartz falls around 1.544 to 1.553, and although quartz has low birefringence relative to many gem materials, the contrast between the purple and yellow zones creates dynamic optical interplay when light travels through the stone. The emerald cut on this specimen uses broad, flat step facets and a large table that return broad flashes of light and accentuate the color separation, producing a type of scintillation and flash that is distinct from the pinpoint brilliance of brilliant cuts. The excellent polish amplifies this effect by reducing surface scatter and allowing light to enter and exit cleanly across large facet planes. Because the stone is transparent and the clarity grade is very very slightly included at eye level, there is minimal internal disruption to the travel of light, which means the reflections and color contrast remain uninterrupted and vivid. In practice, rotating this gem under a light source reveals sweeping bands of purple and yellow as facets align, and the interaction between color zones and facet planes creates an elegance of flashed color that cannot be replicated by single tone gems.

For the educated buyer, this ametrine offers a compelling combination of gemological integrity, aesthetic versatility, and provenance backed value. Large, clean bi color ametrines of this scale and quality are uncommon, and the 8.49 carat weight together with the substantial dimensions of 15.64 by 12.60 by 6.20 mm make this an excellent candidate for a high impact ring or a bespoke pendant where the stone can be displayed with minimal metal coverage to maximize light interaction. The medium intense coloration is particularly desirable because it balances saturation and wearability, avoiding the heaviness that can occur with over saturated material while maintaining strong visible color contrast. Heat treatment is a standard and widely accepted enhancement for ametrine, and when disclosed as here, it is fully compatible with long term wear and stability. Madagascar origin is significant because this source has produced some of the largest and cleanest crystals in recent years, providing a different market niche from the historic Bolivian material, and this provenance will be of interest to collectors who value documented supply chains. At The Natural Gemstone Company we provide full disclosure on treatments and origin, and we are able to supply additional photographic detail and gemological reporting upon request, so that the buyer can verify the characteristics and plan a setting that takes full advantage of the stone position and cut. In summary this emerald cut bi color ametrine is a rare and scientifically interesting specimen, its structure and cut combine to create a distinctive scintillation and color play, and it represents a strong choice for collectors and connoisseurs seeking a statement gem with transparent provenance and enduring wearability.