7.79 Ct. Cabochon Moonstone from Ceylon (Sri Lanka)

This listing from The Natural Gemstone Company presents a single, translucent white moonstone weighing 7.79 carat, with a round outline and precise dimensions of 11.23 x 10.98 x 8.37 mm, cut as a classic cabochon. The gem exhibits a near colorless body tone, classified as near colorless in color intensity, and an eye level clarity grade of very slightly included, evaluated without magnification. The cabochon profile is substantial, with the 8.37 mm height producing a high dome that favors internal light scattering, and the near equality of the 11.23 mm and 10.98 mm diameters confirms a true round outline suitable for symmetrical settings. The surface finish is graded excellent polish, indicating meticulous lapidary work to remove milling lines and to achieve a smooth, reflective dome. Enhancement status is none, the stone is natural and untreated, and origin is Ceylon Sri Lanka, a source noted for fine quality feldspar gemstones. These core specifications have been prioritized for technical review by connoisseurs and lapidaries, and they form the primary basis for assessment, valuation, and design planning.

From an optical and material science perspective this moonstone displays the adularescence that defines fine specimens of orthoclase and albite intergrowths, with internal lamellar microstructures producing a soft bluish white sheen that moves across the dome with changing light angles. The translucency is uniform, permitting subsurface light diffusion without significant opacity, which allows the adularescence to be perceived as a floating light band rather than a surface reflection. The two main variables that determine the quality of adularescence are the regularity of the albite lamellae and the absence of disruptive inclusions, and in this piece the very slightly included clarity grade indicates only minor internal features such as minute fluid pockets or fine cleavage traces, none of which materially disrupt the sheen when viewed at normal observation distances. The near colorless body contributes value by minimizing competing body color, allowing the adularescent flash to remain crisp, and the excellent polish reduces surface scatter that can wash out the effect. Under directional light the dome reveals a pale bluish white flash centered near the apex, with subtle secondary warm reflections toward the base, consistent with high quality Ceylon moonstone material.

The cabochon cutting and finishing techniques employed emphasize controlled dome curvature, symmetrical axis centering, and careful removal of surface pits or nicks, all of which preserve the integrity of the adularescent band and provide a stable profile for mounting. The cutter selected a higher than average dome to maximize internal light travel, a choice that increases visual depth and enhances the floating sheen, while maintaining proportional diameter to height ratios that suit both bezel and prong assemblies. The girdle is smoothly finished and gently rounded to facilitate secure bezel seating and to minimize contact points that could create stress concentrations along perfect cleavage planes. For jewelry design recommendations, this stone is ideally suited to a bezel mounted ring or a shadow box pendant, positions that protect the dome from direct knocks and allow the stone to be viewed against a light background to best display adularescence. If set in metal, options such as 14 karat or 18 karat yellow gold will introduce warm contrast that can emphasize the stone's subtle warm underglow, while palladium white metals will preserve the cool bluish sheen. Considerations for size and finger proportion indicate the 11.2 mm diameter will present as a bold solitaire ring or a central pendant element, and the 8.37 mm dome height should be accounted for in shank profile and bail clearance.

Handling, care, and provenance notes are essential for long term preservation and collector confidence, and The Natural Gemstone Company provides full disclosure on treatment and origin, confirming no enhancement and Ceylon Sri Lanka provenance. Moonstone has a Mohs hardness in the 6 to 6.5 range and a perfect cleavage in one direction in the orthoclase component, therefore mechanical impacts and sudden temperature shifts should be avoided, and ultrasonic cleaners and steam cleaning are not recommended for routine maintenance. Gentle cleaning with warm soapy water and a soft brush, followed by drying with a lint free cloth, will maintain the polish and the optical effect without risk. For appraisal and certification work, the documented measurements, carat weight, cut description as cabochon, clarity grade as very slightly included at eye level, color intensity as near colorless, polish as excellent, no enhancement, and origin as Ceylon Sri Lanka provide a complete technical profile suitable for gemological reports and insurance documentation. For bespoke mounting, volume orders, or to request additional directional images or viewing videos of the adularescence in motion, please contact The Natural Gemstone Company, where our lapidary and sales specialists can advise on setting orientation, matching pairs, and conservation best practices to ensure that this 7.79 carat moonstone performs optimally in any finished piece.