ChloBo Earring Collection Sterling Silver Hoop Earrings With Open Star Charm Pendants. Our Open Star Hoop Earrings are a medium size style at 18mm and made with solid 925 sterling silver. This ever-stylish design pairs perfectly with our ChloBo studs. The star charm is worn as a symbol of hope and guidance. We are all on a path to reaching our ultimate destiny, wear the star as a reminder to stay patient and trust the journey. Each piece of ChloBo Jewellery has been approved by AnchorCert Protect. AnchorCert Protects against all known metal allergens, making it safe for your skin, even if you already have allergies. Diameter is approximately 18mm, with a hinge and clip fasten for a comfortable fit.