Moonstonerefers to a semi-translucent stone that is made of albite and orthoclase feldspar. Moonstone is the best-known gem variety of orthoclase feldspar. It is usually polished as a Cabochon, or Bead, and has even been carved with a moon face.
It is an important gemstone because of its sheen, known as schiller. The most desirable colour is blue or whitish blue, but moonstone can be colorless, also occurs in gray, yellow, orange, white, pink, green, brown, or even reddish.
Moonstone is usually set as a Cabochon. Moonstone was very popular early in the 20th century and was extensively used in Art Nouveau jewelry. Moonstone has a hardness of 6 and a specific gravity of 2.57. It is monoclinic; it has one two-fold axis of symmetry.
There are three (3) types of Moonstone:
1. Adularia - a common type of moonstone.
2. Oligoclase
3. Labradorite and Albite - rare forms of Moonstone
Moonstone shows an almost magical play of light as its characteristic feature. It owes its name to this mysterious gleaming which appears different whenever the stone changes its position in movement.
In India, it is considered a sacred and magical gemstone which is also appreciated as a "dream stone”, as it is supposed to bring about sweet and beautiful dreams.