This 12 MM Non-pierced Omega Back Earrings is 14K Yellow Gold. Approximate item weight is 3.63 grams. Length is 16 MM. Width is 12 MM. Earring closure is non pierced. Caring for Your Gold Jewelry: to keep gold shining and scratch-free, avoid contact with chlorine and other harsh chemicals. Do not wear jewelry during rough work and be sure to store it in a fabric jewelry box or pouch. To clean gold jewelry, use warm water, a mild soap, and a soft-bristled brush, if needed.