Popular belly button ring materials generally align with the same types as earrings or other body jewelry, like titanium, gold, stainless steel, and sterling silver.
Some newer belly ring designs make use of softer materials like silicon or acrylic, and may feature properties that make them hypoallergenic navel rings. Belly rings can feature details like mounted gemstones, dangly chains, and cute charms made of glass, metal, acrylic, and sometimes wood.