Materials Used Barbell jewelry is found in many types of metal and non-metal options. Starter piercings require surgical grade metals such as 316 L stainless steel for proper healing. Titanium is the preferred option for users with allergy or sensitive skin issues. Many people choose plastic for tongue piercings in order to avoid causing damage to teeth while eating. BioFlex and acrylic are among the safest, most hygienic non-metallic options.