The Starlight Collection features a twinkling fusion of trillion-cut Ammolite and 925 Sterling Silver, inspired by the diffusing light of stars. A or AA grade Ammolite 16mm x 15.9mm trillion Ammolite ring 925 Sterling Silver Accented with 1.7mm White Topaz Ring dimension: 18.2mm x 17.8mm Like all gemstones, Ammolite should be treated with care and attention. -Avoid exposure to direct heat. -Do not over-expose to water. -Avoid hard impact to the stone -Do not clean in ultrasonic cleaners -Use a soft, none-abrasive cloth to clean your Ammolite jewellery.