Details Lola Brooks 18k yellow gold & Ethiopian opal cushion pendant, 11.27ct. The bezel-set stone measures approximately 3/4″ x 5/8″ & hangs from an 18", 18k yellow gold chain. - Ethiopian opal, 11.27ct - 18k yellow gold - 18" total length Care Ethiopian opals are hydrophane, which means they can absorb water if immersed which can change their appearance and make the opal's flash disappear. They should not be worn in water.