18 Inch Chain. All of our jewelry chain is made with gold-plated iron, silver-plated iron, and bronze-plated iron. To keep your jewelry clean, wipe with a soft cloth or cotton ball. Never use jewelry cleaner on Coastal Threads jewelry. Store each of your pieces separately or by hanging them. Protect the plating of your jewelry by removing it while swimming, showering, exercising, washing hands, and before applying perfume, lotion, or hair products.