Large Celtic Shield Knot Protection Powers Amulet Snowflake Obsidian Lucky Donut Pendant 18 Inch Necklace Best Amulets Collection. Unique Celtic Shield Knot Amulet Lucky Coin Style Donut Pendant Necklace. Donut Size: 40 mm. Unique Celtic Knot Bail is made from Silver-Tone Base metal. Ready to wear with Beautiful Link Style Stainless Steel 18 inch Chain Necklace. The Natural Properties of Mined Gemstones define the Unique Nature of each piece and no two pieces are every alike. Comes with Gift Style Packaging.