Amulet Golden Pyrite Iron Lucky Coin Shaped Donut Protection Magic Power Pendant Adjustable Cord Necklace Size: 30mm (a little over an inch) Very Popular Lucky Coin Shaped Donut Charm Pendant Necklace. Made from Genuine Golden Pyrite Iron Gemstone Crystal. Necklace Size: Adjustable Cord, Shortest: 15 inches, Longest: 24 inches Comes in Branded Packaging.