These sweet 4mm round Australian Opal studs are perfect for the ones who love dainty earrings. They are so sweet and light wear, perfectly created for the sweet ears of our little ones. We recommend you order the flat back variant if you are buying a pair for your child, they're more comfortable and easy to wear. Also the flat backs are perfect for those who have piercing on the upper part of their ears like the helix, mid helix or lower helix for example. Keep in mind that because we use natural stones the color and iridescence of the Australian Opals may vary.