Copper plated TierraCast® 9mm Celtic rivetables aka decorative washers for riveting. Great for leather! 3mm center holes are perfect for use with TierraCast rivets. Antiqued copper plated components are often used to give jewelry a classic and vintage look. Although these Celtic knot findings are designed as rivet accents, they are also great as small choker centerpieces, as well as links or connectors for a wide variety of Celtic jewelry designs.