Moonstone

Moonstone is in the mineral composition group of silicate, and the sub-mineral group of tectosilicate. A significant portion of the earth's crust is composed of minerals from the feldspar group such as Moonstone, Amazonite, Oligoslase, and labradorite, most of which are not gemstones. In India, moonstone is considered to be a sacred stone and has a floating light effect and sheen called adularescence, compared to the light of the moon. This phenomena results from alternating layers of two kinds of feldspar, namely orthoclase and albite, which cause light to scatter. Rare forms of moonstones are from Plagioclase Feldspars Albite and Labradorite. It is a popular gem and comes in an assortment of colors. It is usually set as a cabochon and extensively used in making jewelry. It is monoclinic; it has one two-fold axis of symmetry. Moonstone specimens commonly exhibit chatoyancy, and sometimes display a strong cat's eye.