Moonstone is a gem that derives from the feldspar group. It is a variety of orthoclase, and most famous for its adularescence effect. Alternating feldspar layers build up within the stone during formation, which allows light to glide across the layers of the gem, producing this signature effect. It is usually of a blue, silver, or white color. Sri Lankan moonstone is a luminous delight! Possessing an enigmatic sheen that shifts and shimmers across the stone's surface, few gemstones match the romance and mystique of moonstone.