10.74 Ct. Cabochon Moonstone from Ceylon (Sri Lanka)

One exceptional translucent white moonstone, weighing 10.74 carat, is presented by The Natural Gemstone Company, exhibiting an oval outline with dimensions of 15.49 x 13.01 x 7.14 mm. The gem has been shaped as a cabochon, a traditional cut for feldspar group gemstones, and displays a near colorless body tone that allows internal light play to be readily visible. Clarity has been evaluated at eye level as eye clean, indicating that no inclusions are detectable without magnification, and the surface shows an excellent polish that enhances both luster and adularescence. There has been no enhancement to this specimen, and its documented origin is Ceylon Sri Lanka, a locality known for producing high quality moonstone material with clean body tones and strong optical effects.

The weight of 10.74 carat is a pivotal attribute in assessing both rarity and value for moonstone. Unlike gem species where precision faceting can increase apparent size, moonstone value is driven by the presence of clean, translucent material at larger sizes. Rough feldspar suitable for clean cabochons of this scale is comparatively uncommon, so a single, intact piece of 10.74 carat that is translucent and eye clean represents a significant portion of market supply for high grade material. Weight contributes to rarity in a non linear manner, with premium increments commonly applied once stones exceed size thresholds that are rare for a given clarity and body color. For designers and collectors this means the 10.74 carat size is not merely larger by proportion, it occupies a higher scarcity class, and commands a price differential that reflects both the technical challenge of producing such a clean cabochon and the desirability of a larger adularescent surface.

From a technical optical perspective the cabochon dome and the measured thickness of 7.14 mm play a direct role in the quality of adularescence observed in this moonstone. Adularescence arises from the submicroscopic lamellar intergrowth of orthoclase and albite within the feldspar structure, producing coherent scattering that moves across the dome with changes in light angle. A well proportioned cabochon dome maximizes this effect by providing a smooth curved surface that allows the internal lamellae to project a coherent sheen, and the 7.14 mm profile on this oval permits a pronounced and even sheen rather than a thin or chalky display. The near colorless body tone minimizes interference from background color, so the sheen reads as a clean white to slightly bluish flash depending on lighting and orientation, and the eye clean clarity enables unobstructed light paths, preserving the integrity of the adularescent band. The oval shape, cut with attention to symmetry and polish, yields directional movement of the sheen that can be emphasized or restrained by the choice of setting orientation.

From a lapidary and setting perspective the craftsmanship of this cabochon is evident in its smooth curvature, even girdle, and excellent polish, and those attributes inform practical recommendations for mounting. The substantial thickness of the dome supports wearable settings, and the oval 15.49 x 13.01 mm footprint is versatile for both rings and pendants. For optimal presentation and protection a bezel setting is recommended, as it secures the entire girdle and guards the stone against lateral impacts that can chip polished feldspar surfaces, and a low profile prong mounting may be employed if the bezel is engineered to protect the dome edge. Designers should consider metal temperature and soldering protocols during setting to avoid localized thermal stress, and polishing and finishing after setting should be performed with care to preserve the excellent surface polish. The natural state of the stone with no enhancement further increases its appeal to collectors seeking untreated material and simplifies disclosure in sales documentation.

Provenance from Ceylon Sri Lanka contributes to both historical and market considerations, as material from this region is often sought for its clean body tones and appealing adularescence. When combined with the technical attributes of translucency, eye clean clarity, excellent polish, and the substantial weight of 10.74 carat, this moonstone occupies a premium category. Market valuation for moonstone integrates these factors, and the premium payable for larger eye clean specimens increases disproportionately as comparative supply narrows. At The Natural Gemstone Company we document each of these technical characteristics to support informed purchasing, and this 10.74 carat white moonstone represents a rare opportunity for connoisseurs and designers to acquire a natural, untreated cabochon that balances optical performance with a size that is uncommon for such high clarity material.