5.48 Ct. Bi Color Ametrine from Brazil

This transparent bi color ametrine from Brazil presents as a finely faceted oval weighing 5.48 carats, with dimensions 11.85 by 9.51 by 8.61 millimeters. The cutter employed a mixed brilliant faceting scheme to balance scintillation and color retention, with a polished table plane that maximizes light entry and a pavilion geometry aimed at strong return through the crown facets. Color zoning is distinct and well balanced, exhibiting warm golden citrine tones transitioning into cool amethyst violet across the stone, with intense color intensity that remains saturated under both daylight and warm incandescent lighting. Clarity is graded as very very slightly included when evaluated at eye level, indicating only minor internal characteristics that do not interfere with transparency or overall brilliance, and the surface polish is excellent, delivering crisp facet junctions and mirror like facet planes. The material has been heat treated to stabilize color and enhance saturation, a standard enhancement for ametrine that preserves the natural bicolor zoning while improving visual uniformity and durability. As a provenance detail, this example originates from Brazil, where the geologic conditions produce well zoned ametrine crystals that respond predictably to precise cutting and thermal treatments.

From a gemological and lapidary perspective, the mixed brilliant cut on this oval was executed to emphasize both flash and color separation, with a brilliant facet layout on the crown to generate lively scintillation, and a controlled pavilion architecture that moderates internal light paths to heighten color contrast between the citrine and amethyst areas. The length to width ratio is approximately 1.25, producing a classic oval silhouette that is versatile for ring and pendant proportions, and the measured height results in a depth that translates to a depth percentage of about 80.6 percent when compared to the average of the length and width dimensions. This relatively deep cut concentrates color and can yield dramatic saturation and apparent size when set in open backed or well ventilated settings, while also requiring careful seat design to avoid undue stress on the pavilion during mounting. Facet symmetry and junction precision are apparent in the crown star and upper girdle facets, and the clean girdle profile and excellent polish support high quality finishing techniques, which together make the gem well suited to fine jewelry applications that demand optical performance and longevity. The very very slightly included clarity grade means that loupe and microscope examination will reveal only small inclusions that are stable and do not compromise structural integrity, allowing for confident setting in prong, bezel, or closed gallery configurations without the need for extensive reinforcement.

The versatility of this 5.48 carat Brazilian ametrine lends itself to a broad range of customized jewelry settings, and The Natural Gemstone Company can advise on design choices that exploit the stone geometry and color zoning. For an engagement or statement ring, a four prong or six prong solitaire will showcase the oval silhouette while minimizing metal coverage of the color boundary, and an east west mount will emphasize horizontal color banding for a modern aesthetic. A low profile bezel with a narrow channel and under gallery cutouts will protect the girdle and pavilion while permitting light to enter from the pavilion, preserving the visual interplay of citrine and amethyst. For pieces that call for optical drama, a halo of small brilliant cut side stones can frame the oval and increase perceived size, while a three stone configuration with calibrated amethyst and citrine side stones can reinforce the natural bicolor narrative. Pendant and drop earring settings benefit from orientation options that place the bi color boundary either vertically or diagonally, creating dynamic color change with movement. Metal choices will materially affect perceived color, with yellow or rose gold accentuating the citrine warmth, and white gold or platinum offering a cooler contrast that highlights the amethyst side. Technical considerations for fabrication include a secure seat for the deep pavilion, potential use of a protective bezel lip for frequent wear rings, and allowance for light windows in closed back settings to optimize brilliance. The Natural Gemstone Company is available to assist with bespoke design, CAD renderings, and setting recommendations tailored to the unique proportions and optical behavior of this oval ametrine, ensuring that the finished jewelry unifies aesthetics, structural integrity, and the striking bicolor character of the gem.