K18 2mm Ball Stud Earrings - Color: Yellow Gold - Design: Simple stud earrings - Material: K18 ★ The backings are silicone. ⭐ Purchased at a jewelry store! ★ Disinfected with alcohol ⭐ About the markings I originally had silicone backings, but I snagged them and lost them. The markings were on the backings. There are no markings on the posts, but apparently, there are cases where the markings are on the backings and not on the posts. Purchased at a jewelry store! ★ Please consider purchasing if you understand. Thank you for looking.