Polymer clay is generally durable and a bit flexible, but handle and store with care to avoid breakage and scratches. Wipe polymer clay clean with a soft cloth with mild soap and water. Avoid harsh chemicals.
Sterling silver and brass may naturally tarnish over time. Keep metal dry, avoid high humidity, and store in an air-tight container to help prevent tarnish. Wipe with a polishing cloth to remove tarnish and restore shine.