It is also called moti and is a gemstone of moon. It can be worn in time when the phase of a person is under moon transit. In general, anyone can wear it but those with a favorable moon in their horoscope will benefit a lot.
It is said to bring a stable mind avoiding fickle-mindedness. It is also said to remove sins of the wearer and bring in prosperity. It should be worn in silver (in little finger) or necklace on Monday evening after offering prayer to Lord Shiva and moon.