Silver or Gold Microscope Necklace. Show your love for molecular biology! This adorable necklace is a perfect necklace for your science and biology enthusiast. This silver microscope pendant can be placed on a silver chain between 16-20 inches in length. The model is wearing a 17-inch chain. The pendant measures 1.4 x 0.8 inches. Purchase includes an informational card, a natural jewelry box, and gift packaging. Add-on extender: https://www.etsy.com/listing/197483038/add-on-necklace-extender-chain-with Necklace longer than 20 inches: https://www.etsy.com/listing/196689227/extend-my-necklace-up-to-30-inches Turn pendant into a keychain or ornament: https://www.etsy.com/listing/1003597263/turn-any-pendant-into-a-key-chain-or ★ ITEM DETAILS ★ Chain: 18-inch Snake in either Sterling Silver or Gold Filled (Your Choice!) Pendant: Stainless Steel Plated with Silver or Gold ★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★ Sterling Silver jewelry is an alloy that contains a mixture of 92.5% pure silver and 7.5% of another metal, usually copper. Sterling silver is safe for sensitive skin; however it must be stored in a dry dark place as overtime it will tarnish. It can be restored with a silver polish cloth. Gold-Filled Jewelry employs a process in which gold is bonded to a base metal alloy such as nickel or brass. All exterior portions are solid gold and safe for sensitive skin.