0.67 Ct. Moonstone from Ceylon (Sri Lanka)

This 0.67 carat, emerald cut rainbow moonstone is a refined and collectible example of fine Ceylon moonstone, measuring 6.94 by 4.26 by 3.18 millimeters. The gem is transparent with a faint body color and displays the soft, multi-hued adularescence for which rainbow moonstone is prized. The emerald cut has been executed to emphasize clarity and to create crisp step facets that channel light along linear planes, allowing the internal sheen and spectral flashes to read cleanly to the eye. Clarity is graded as very very slightly included, evaluated at eye level, and the piece has an excellent polish with no indications of enhancement. Sourced from Ceylon, Sri Lanka, this moonstone benefits from a provenance that is historically associated with strong adularescence and consistently high lapidary quality. At The Natural Gemstone Company we present this stone as an attractive choice for collectors and designers seeking a transparent, untreated moonstone with a classical cut and natural optical effects.

To put the clarity and overall grading in context for an educated buyer, very very slightly included evaluated at eye level communicates that inclusions are minimal and do not materially interrupt the visual appeal when the gem is viewed without magnification. Moonstones are typically graded on a combination of adularescence, body tone, transparency, and presence of internal features. In this specimen, the faint body color and high transparency allow the adularescence to be observed cleanly, while the excellent polish ensures facet junctions and table reflections are tight and well resolved. The emerald cut in feldspar is a deliberate stylistic and practical choice; step facets preserve and showcase the planar nature of the lamellar structures that cause the sheen, and they also minimize over-faceting that can diminish the moonstone’s characteristic glow. The absence of any enhancement increases the stone’s market desirability among connoisseurs who prioritize natural material and stable value.

What makes this rainbow moonstone unmistakable is the pattern and nature of its internal inclusions and intergrowths, which act like a petrographic fingerprint. Moonstone’s adularescence is produced by microscopic lamellar intergrowths of orthoclase feldspar and albite or related compositional variations, and in rainbow moonstone the scattering and dispersion of light from these thin, oriented layers produces multi-hued flashes. Inclusions in this piece include fine planar exsolution lamellae and extremely fine needle-like or tubular features that are aligned with the crystallographic planes. These features interact with the emerald cut’s step facets to generate concentrated bands and flashes of color as the gem is tilted, producing rainbow highlights in addition to the classic bluish or white sheen. The inclusions are not fractures in the sense of structural compromise, but natural growth features that yield optical complexity. They provide a reproducible internal pattern that a trained eye can use to identify the stone’s natural origin and to differentiate it from synthetics or heavily treated material. For collectors, the presence and arrangement of these microstructures is often considered part of the gemstone’s personality, an internal landscape that gives the gem an unmistakable signature.

For an educated buyer assessing value, several points make this moonstone noteworthy. First, it is an untreated natural material from Ceylon, a source with a long history of producing high-quality feldspar specimens. Second, the combination of transparency, faint body color, and very very slightly included clarity grade gives the stone a clean visual appeal while allowing the lamellar adularescence to remain the dominant optical feature. Third, the emerald cut and excellent polish maximize wearable elegance and setability in fine jewelry, making it straightforward to integrate into a bespoke ring, pendant, or pair of matched pieces. Because moonstone belongs to the feldspar family, it has good but not extreme hardness and requires mindful setting and occasional care to avoid hard impacts along its cleavage planes; we recommend protective bezel settings for everyday wear. At The Natural Gemstone Company we can provide detailed photographs, viewing videos under directional light, and optional gemological reporting to document origin, optical properties, and the nature of the inclusions. This moonstone offers the discerning buyer a combination of aesthetic subtlety and geological authenticity, the sort of piece that rewards close inspection and will remain a distinctive and verifiable part of a curated collection.