A pair of black onyx earrings are an affordable and elegant gift. Always appropriate and always in style, black onyx should be in every jewelry box. A pair of black onyx earrings are an affordable and elegant gift. Always appropriate and always in style, black onyx should be in every jewelry box. A pair of emerald earrings are a timeless and classic accessory. You can choose from genuine emerald, or more affordable lab-created emerald.