moon stone - Natural minerals and crystals

Moonstone is widely recognized for its unique optical effect called adularescence. This phenomenon manifests itself as a bluish or white sheen that appears to slide across the surface of the stone when exposed to light. This characteristic is due to the lamellar structure of moonstone, where microscopic layers of orthoclase and albite form alternately, creating light diffraction. Moonstone is found mainly in deposits in India, Sri Lanka, Burma and Madagascar. Its hardness on the Mohs scale is 6 to 6.5, making it relatively tough. In terms of crystallography, moonstone belongs to the monoclinic crystal system, and its crystals can occur as elongated prisms or compact masses. Moonstone is prized for its aesthetics and rare luster. It is often cut en cabochon to maximize the adularescence effect. Mineralogy enthusiasts and collectors particularly appreciate specimens with a variety of colors ranging from milky white to blue, peach, or gray.