MATERIALS - 3D anatomical heart locket is made of solid 925 sterling silver with 14k gold plated. This is a 3D Anatomical Heart Locket. Check out the pictures to see the front and back! The back is flat so it can be engraved if desired. Most local jewellers can engrave it. Dimensions: 32mm x 20mm, 22mm x 14mm. Heart locket comes in a gift box.