Round Cubic Zirconia Stud Earrings

Worn less than 10 times. I believe the gold is genuine 10K since I bought them from a fine jewelry store, but they are so small that I can't see any markings indicating so. I'm guessing they are actually 10K because I usually don't wear anything gold-plated as I have very sensitive ears and am allergic to nickel. I have unfortunately lost one of the backings, but I can include a replacement! No obvious flaws or signs of wear. Please leave me a comment with any questions!