1.50 Ct. Greenish Yellow Sapphire from Montana

This greenish yellow sapphire weighs 1.50 carat, and is presented in a classic round shape with precise dimensions of 6.95 x 6.85 x 4.47 mm. The material is transparent, and it carries a mixed brilliant faceting style, chosen to balance light performance with color saturation. Clarity is graded as slightly included when evaluated at eye level, and color is described as medium intensity, an even field of greenish yellow that shows pleasing vibrancy without overstating saturation. The surface finish is excellent, with a polish that renders facet junctions crisp and reflective. Enhancement has been applied by heat treatment, a widely accepted and professionally executed practice intended to stabilize and refine color and clarity. The sapphire originates from Montana, and The Natural Sapphire Company stands behind its provenance and disclosures, providing full transparency for knowledgeable buyers.

The journey of this gem began in the alluvial gravels and hard rock pockets of Montana, where crystallization conditions favor unique iron and titanium trace chemistries that yield greenish yellow tones. At the mine the rough was assessed for crystal habit, inclusion character, and zoning. Montana sapphires often exhibit internal features such as fine silk, mineral inclusions, and growth zoning, and this piece was selected because its body color showed stable distribution and limited orientation dependent color variance. During rough evaluation, the lapidary determined an orientation that would maximize the visible color when viewed table up, while retaining as much carat weight as possible. This decision required technical tradeoffs, choosing between preserving weight and aligning the pavilion with the optical axis to reduce windowing. The rough was preformed to establish a rounded outline and to remove surface blemishes and fractures that would compromise stability and polish, preparing the material for precision faceting.

Faceting work employed a mixed brilliant approach, combining a modified brilliant crown with a step influenced pavilion, a configuration that harnesses both scintillation and controlled return of light to the viewer. The crown was proportioned with a moderate table, slightly smaller than average for this diameter, to intensify apparent color and to encourage facet play. Star and upper girdle facets were calibrated to create a lively scintillation pattern, while crown angles were set to optimize the balance between brilliance and dispersion. The pavilion was cut with careful attention to depth, achieving a profile that prevents leakage of light through the base and mitigates the windowing effect that can desaturate greenish yellow tones. Facet junctions were executed to meet at precise lines, and pavilion mains were aligned to form a symmetrical light return pattern. The girdle was left sensible to ensure setting security without introducing unnecessary weight. Polishing stages used progressively finer abrasives to reach an excellent polish, producing mirror like facet surfaces that enhance luster and allow the medium color intensity to read evenly. Slightly included clarity at eye level was managed by orienting inclusions toward facet junctions or the girdle where they exert minimal influence on face up appearance, thereby preserving visual cleaness while retaining a natural character typical of Montana material.

From final inspection the finished gem entered the market with full disclosure from The Natural Sapphire Company, presented with origin and enhancement statements that reflect professional lab practices. Heat treatment was documented as part of the provenance narrative, and the gem was evaluated under controlled lighting and magnification to confirm its optical performance. For the collector or client who appreciates technical detail, this sapphire offers a balanced profile, combining a compact 1.50 carat weight with dimensions that support classic mounting options. The round mixed brilliant design adapts well to solitaire settings that emphasize table up color, and also suits multi stone designs where the stone will contribute a stable mid tone of greenish yellow between accent diamonds. Care recommendations include avoiding sudden thermal shock and prolonged exposure to harsh chemicals, routine inspection of the setting to protect the sensible girdle, and cleaning with mild detergents and a soft brush to maintain the excellent polish. The Natural Sapphire Company is available to provide high resolution imaging, facet map consultation, and advise on setting choices that will best utilize the mixed brilliant proportions, and we welcome inquiries from gemologists and jewelers seeking additional data on inclusion orientation, facet angles, or suitability for bespoke mounting.