Adular (lunar stone) is a variety of orthoclase mineral from the feldspar group. Thanks to its composition - alternating layers of orthoclase and albite minerals - an optical phenomenon called "adularescence" (or Shiller) is created when the light falls, making Adula so well known and highly valued.
Adular was named after his discovery, the Adul mountain range in Switzerland. But the most beautiful moonstones come from Sri Lanka, Tanzania and also Madagascar.
Adular has been used in jewelery for thousands of years - records have been preserved since ancient civilizations. E.g. the ancient Greeks and Romans admired and worshiped the lunar stone because they believed it was made of the rays of the moon and connected it with the moon deities.
The Moonstone has also become popular during the Art Nouveau period, when the most jewelry with this gem began to emerge. Even today jewelers and jewelers are very popular and interest in it is constantly growing.
Most often, they are cut into cabochons to excel the beauty of adularescence.
Very rare is the so-called "cat eye" effect in adular.