This rare double-terminated moonstone crystal, originating from Andilamena in the Alaotra-Mangoro region of northeastern Madagascar, represents an exciting new discovery in the world of feldspar minerals. Measuring 27mm x 16.85mm x 11.25mm and weighing 40.6 carats, this specimen is one of the better-terminated pieces we have seen from this important find, combining natural form with optical brilliance.

Unlike traditional moonstone, which is typically translucent and cut en cabochon, this highly transparent crystal displays not only the classic strong blue adularescence but also a striking and distinct orange flash effect—a phenomenon brought out even more vividly by its sharp crystal faces and minimal surface disruption. The piece also features a minor cleaved side, adding character without compromising the remarkable clarity and form.

Analyzed and confirmed as a plagioclase feldspar within the labradorite variety, this material differs from the typical orthoclase-based moonstones. Its internal structure of microscopic albite and labradorite lamellae creates vivid interference colors when viewed under shifting light, producing an ethereal play of blue moonlight accented by fiery orange flashes—an exceptionally rare optical combination.

Nearly flawless, this piece is not only an incredible collector-grade specimen but also represents top-tier facet rough for those daring enough to unlock its full potential through precision cutting. Whether admired as a natural treasure or fashioned into a world-class gem, it stands as a luminous testament to Madagascar’s continued contributions to rare and phenomenal gemstones.