12.47 Ct. Cabochon Moonstone from Ceylon (Sri Lanka)

This listing presents a single translucent grey moonstone, precisely cut as an oval cabochon for optimal adularescent display, weighing 12.47 carats, with exact dimensions 16.59 by 12.32 by 8.52 millimeters. The length to width ratio of approximately 1.35 provides a classical oval silhouette that is well balanced for both ring and pendant designs, and the measured depth represents approximately 51.4 percent of the length, a proportion that yields a substantial dome while maintaining elegant profile lines. The cut is a traditional high dome cabochon, with an apex that is accurately centered and transitions that are smoothly feathered to the girdle, this geometry maximizes the internal scattering of light and produces a soft, uniform glow across the surface. Clarity is graded as very very slightly included, evaluated at eye level, indicating inclusions are minute and do not detract from the overall translucency and optical effects. Color intensity is described as very light, presenting as a delicate grey field that will serve as a versatile neutral foundation in calibrated or bespoke settings. Origin is Ceylon Sri Lanka, and there has been no enhancement applied, which assures natural provenance and integrity of the material, a point that discerning buyers and connoisseurs will appreciate when assessing long term value and stability.

From a gemological perspective this specimen exhibits the characteristic adularescence produced by alternating layers of orthoclase and albite, a lamellar microstructure that scatters incident light in a directional sheen. The cabochon profile has been selected specifically to accentuate that sheen, with a dome height sufficient to allow for coherent internal reflection without creating zones of optical wash out. Surface finish is graded excellent, with a polish that yields a vitreous to slightly pearly luster on the dome, and an absence of polishing pits or facetting remnants. Optical parameters for moonstone materials of this type typically fall within refractive indices near 1.518 to 1.526, with very low birefringence on the order of 0.005 to 0.010, and a specific gravity in the mid two point five range, these values underpin the way light is transmitted and scattered through the cabochon and inform setting and mounting choices from a technical standpoint. The translucency is uniform, allowing light to penetrate and reveal subtle depth within the body while preserving a serene surface sheen that is desirable for high quality collector and design use.

Craftsmanship details are apparent in the symmetry and finish of the piece, the oval outline is true to form, the table region is smoothly convex, and the girdle has been left proportionate to accommodate common bezel and prong settings without risk of creating stress points. As a cabochon, the stone benefits from a protective setting that minimizes lateral impact, therefore a fully enclosed bezel or hybrid bezel with secure seat is recommended for rings that will see daily wear, while lower stress applications such as pendants and earrings can exploit the stone in more open settings to showcase its translucency. Because moonstone has a hardness of approximately six to six and a half on the Mohs scale, care in mounting is advised, noting that sharp prong contact at thin girdles can be avoided with a well designed seat. Cleaning is best managed with warm soapy water and a soft brush, avoiding prolonged exposure to heat and aggressive ultrasonic or steam methods that can induce thermal stress or exacerbate existing fissures, routine inspection of the setting is advised to ensure continued security given the stone density and cabochon profile.

The Natural Gemstone Company presents this Ceylon grey moonstone as a technically refined specimen suitable for designers, collectors, and connoisseurs who value natural, untreated material with controlled optical character. The combination of a well proportioned oval outline, a high quality cabochon cut, an excellent polish, and very very slightly included clarity evaluated at eye level makes this gem a compelling choice for pieces that prioritize subtlety and technical excellence over overt color saturation. For bespoke projects that require matching pairs or for clients seeking certification level documentation, our team can assist with additional measurements and imaging, and we can advise on mounting strategies that preserve the integrity and maximize the visual performance of the stone. This moonstone embodies the understated refinement that our clients expect from The Natural Gemstone Company, and we welcome inquiries to discuss how it can be incorporated into your next design.