Natural Moonstone · 4.210 ct · Oval Cabochon · Blue Adularescence

This individually natural Moonstone weighs 4.210 carats and has been fashioned into an elegant oval cabochon, polished on both sides. The gemstone displays a milky white body appearance accompanied by a combination of blue and subtle yellowish adularescence, creating a distinctive floating sheen that changes with lighting and viewing angle.

Measuring approximately 11.2 × 9.4 × 5.0 mm, the stone has a balanced oval profile and a smooth domed surface that provides an effective presentation of the natural feldspar material. The cabochon form is particularly well suited to Moonstone because it allows the adularescent effect to move visibly across the surface rather than relying on conventional facet brilliance.

Although recorded as transparent, the milky internal appearance produces areas of softer light transmission and gives the gemstone additional visual depth. The contrast between the white body, blue sheen and slight yellowish optical influence creates an individual colour expression specific to this specimen.

Adularescence

Adularescence is the characteristic optical phenomenon associated with Moonstone. It results from the interaction of light with extremely fine internal feldspar layers. These microscopic structures scatter and interfere with incoming light, producing the characteristic floating or cloud-like sheen visible beneath the surface.

In this gemstone, the phenomenon presents predominantly as a blue adularescence with a subtle yellowish component. The position and intensity of the effect naturally change as the stone is tilted or viewed from different directions.

The cabochon has been polished on both sides, allowing the internal structure and optical effect to be appreciated from multiple viewing angles.

The overall cutting quality is assessed as Good, with Good symmetry, Good polish and Good luster, resulting in a balanced and pleasing overall presentation.

No indications of heating or other treatments have been recorded for this gemstone. It is therefore presented in its naturally documented state.

Moonstone belongs to the feldspar group and has a hardness of approximately 6 on the Mohs scale. Its birefringence is approximately 0.005–0.006, while material identified within the orthoclase feldspar family crystallises in the monoclinic crystal system.

As a natural gemstone, internal inclusions, fine lamellar growth structures, subtle milky variations, fissures or minor surface-reaching characteristics may occur. These features developed during the natural formation of the material and may influence the distribution and appearance of the adularescent sheen.

With its 4.210 ct weight, softly milky white body and attractive combination of blue and subtle yellowish adularescence, this natural Moonstone offers a distinctive expression of feldspar’s characteristic optical behaviour. Its balanced oval cabochon form and double-sided polish make it particularly suitable for gemstone collectors, bespoke jewellery or designs where the changing adularescent effect can remain central to the presentation.