Size of bead: 10mm Giant Clam Also known as Ōgigai (fan shell), Shako. They inhabit shallow waters of coral reefs in tropical to subtropical seas and are the largest species of bivalve. Includes the Tridacna gigas. It was named for its appearance, which resembles a spread fan. Giant clams are rare organic gemstones, white like jade, and are Buddhist relics. Giant clams, pearls, coral, and amber are known as the four major organic gemstones. In Chinese Buddhism, they are revered as one of the seven treasures along with gold, silver, lapis lazuli, agate, coral, and pearls. Giant clams are one of the seven treasures of Buddhism, and it is said that chanting the nenbutsu using a giant clam rosary can bring twice the merit. It is said to calm the mind, be effective against insomnia, and is good to wear for a long time. It is said to heal mental fatigue and be good for visual impairment, and it is also said to have the power to improve fortune, maintain health, and ward off evil. Meaning of 108 Buddhist beads: To remove the 108 earthly desires and wish for liberation from suffering, peace, and joy.