This special Hamsa pendant is made of genuine dark blue Opal . The size is 13 mm ; on the sides there is a hole where the chain is slides through. The chain is a fine solid 14K yellow gold box chain. Size of necklace is 16 1/2 inch. Also available in 14K white gold. Cute! The Hamsa Hand (Arabic) or hamesh hand (Hebrew) is an old and still popular apotropaic amulet for magical protection from the evil eye. The words hamsa and hamesh mean "five" and refer to the digits on the hand. Referred also as hand of Fatima and hand of Miriam. For centuries the Hamsa has been used as a symbol of Good luck and shields its owner from the curse of the evil eye. The Hamsa's positive energy draws happiness, riches and health.