Orthoclase is an important tectosilicate mineral, which forms igneous rock. It is also known as alkali feldspar and is common in granite and related rocks. According to an Indian legend this stone was appearing on the beach of the sea only five times a year and only on the full moon nights. The lucky girl that was able to find one was destined to marry a king. The stone is intimately linked to the feminine universe, to growth and evolution and is the personification of the light that brigs life. Zodiacal sign: Cancer.