Yin Yang BA GUA Eight Trigrams Amulet Green Quartz Leather Pendant Necklace Best Amulets Collection. Yin Yang BA GUA Eight Trigrams Amulet Green Quartz Magic Gemstone Stainless Steel Circle Spiritual Powers Pendant Leather Necklace Yin Yang BA GUA Eight Trigrams Amulet Green Quartz Leather Pendant Necklace Gemstone Circle Size: 30mm (1 1/4"). Made from Natural Gemstone and holds permanently attached Yin Yang BA GUA Stainless Steel Charm. Ready to Wear with Beautiful 18" Black Leather Cord Necklace. Comes with Branded Packaging.