Moonstones for June Birthdays

Moonstone  Cabochon

       The name moonstone derives from the stone's characteristic visual effect, called adularescence (or schiller), which produces a milky, bluish interior light. This effect is caused by light diffraction through alternating layers of orthoclase and albite within the stone. The diffracted light varies from white to blue, depending on the thinness of the albite layers. More technically, this micro-structure consists of regular exsolution layers (lamellae) of different alkali feldspars (orthoclase and sodium-rich plagioclase). 

        The moonstone in legends, is reputed to be potent in providing its possessor with good fortune. It was believed that if it were held in the mouth it would refresh the recollection of the holder. Ancient apothecaries used it for the cure of epilepsy. The Romanticists believed that during the waxing of the moon it was an efficacious love charm, and during its waning it would enable the wearer to foretell the future. 

        Gemologists classify moonstone into several distinct varieties. Blue moonstone represents the finest variety of labradorite moonstone, with high transparency and strong blue adularescence. Blue moonstone can be found in Myanmar (formerly Burma), India, Madagascar, Malawi, Sri Lanka, and Tanzania. Labradorite moonstone belongs to the plagioclase feldspar group and forms within the triclinic crystal system, appearing in colorless, white, slight orange, or green varieties with a blue sheen. Orthoclase moonstone belongs to the monoclinic crystal system and displays a mystical white glow in colorless to white, orange, yellow, or brown hues. Gem enthusiasts often refer to adularescent labradorite with a multi-colored glow as "rainbow moonstone," which is colorless and highly transparent. Adularia, named after the Adular Mountains of Switzerland, forms in hydrothermal veins in mountainous regions as colorless to white, cream, pale yellow to pink, or reddish-brown, glassy, prismatic, twinned crystals that frequently display a white to blue sheen.

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