1.78 Ct. Cabochon Moonstone from Madagascar

This translucent blue flash moonstone from Madagascar is a well-proportioned, round cabochon weighing 1.78 carats, with precise dimensions of 8.35 by 8.39 by 3.87 millimeters. The cabochon cut has been executed to emphasize adularescence, producing a cool blue sheen that moves across the dome with changes in light and orientation, a key optical effect that defines high-quality moonstone. Clarity is graded as very slightly included at eye level, which is typical for natural feldspar and does not detract from the overall visual appeal; instead, the minor inclusions can contribute to the stone's internal character and authenticity. Color intensity is medium light, providing a pleasant balance between body tone and the visibility of the blue flash, and the piece exhibits an excellent polish, resulting in smooth, reflective surfaces and a well-defined, symmetrical outline. The moonstone is untreated, with no enhancements, and its documented origin in Madagascar further supports its provenance, as this locality is known for producing material with attractive adularescence and stable supply channels.

From an investment perspective, several objective attributes make this specimen noteworthy. Untreated gemstones with natural optical phenomena, such as a pronounced blue adularescence, occupy a desirable segment of the market, because they combine aesthetic rarity with predictable grading factors. The 1.78 carat weight situates this piece above many smaller sizes that dominate the market, granting it greater interest from both collectors and designers seeking a focal stone for bespoke jewelry. Provenance from Madagascar adds value due to the reputation of the source, and the absence of enhancements simplifies valuation, as untreated material generally commands stronger long-term interest than treated equivalents. Supply considerations also play a role, while Madagascar continues to produce moonstones, high-quality blue flash material in attractive sizes and well-executed cabochons is limited relative to overall demand, supporting steady price resilience. Taken together, the stone’s combination of size, visible adularescence, excellent polish, and untreated status creates a profile that is consistent with items that have historically shown appreciation in specialist and collector markets.

When evaluating future appreciation, it is important to consider the drivers that influence secondary market performance in colored gemstones, and how this moonstone aligns with them. Key valuation drivers include optical performance, treatment status, provenance, cutting quality, and market trends. This moonstone demonstrates strengths across these criteria, with a directed cut that maximizes the adularescent effect, clean finish, and documented Madagascar origin. The broader market for natural, untreated gems has been supported by growing consumer interest in artisanal and ethically sourced materials, alongside steady demand from independent jewelers and private collectors who favor distinctive optical properties over mass-produced alternatives. While moonstone historically occupies a niche compared with traditional investment gems such as sapphire, ruby, and emerald, the segment for high-quality adularescent stones has shown selective appreciation, particularly for pieces that combine attractive size and strong visual character. Prospective buyers should, however, weigh these positive indicators against the inherent variability of gemstone markets, and consider obtaining a gemological report for formal documentation, and retaining detailed provenance and photographic records to enhance future marketability.

To preserve the condition and investment potential of this moonstone, practical care and presentation are advisable. Avoid exposure to sudden temperature changes, high heat, and harsh chemicals, and store the stone separately from harder gems to prevent surface abrasion, as the cabochon polish and dome shape are central to its visual impact. For jewelry settings, designs that protect the girdle and cabochon dome, such as bezel or partial bezel mounts, will reduce the risk of chipping while allowing the adularescence to remain visible. The Natural Gemstone Company provides this moonstone as a documented, untreated specimen, and can assist with supplementary documentation and recommendations for setting and care to support long term preservation and potential appreciation. While no investment is guaranteed, this moonstone presents a coherent set of attributes that align with the factors collectors and connoisseurs typically consider when assessing long term value in natural, optical phenomenon gemstones.