Natural Stone High-Grade Silver Opal Ring. Size approximately: 4.5mm*18.5mm*thickness 4mm; Metal Material: silver925 silver, stamped with s925; Comes with a bag, product number A2225; Ring Size: Adjustable free size. Recommended for free size rings: ● Those unsure of their ring size "Don't know my ring size..." ● Those whose rings become tight due to swelling at night Opal [October Birthstone] October is the peak of the harvest season, and harvest festivals are held in Europe and America. As if to show the joy of the harvest, opal, which brings happiness to people and has the meaning of "joy, comfort, and overcoming sorrow to gain happiness," is the October birthstone. Opal is a lucky charm. [About Opal Rings] Opal is characterized by its beautiful iridescent play of color. The secret lies in the "play-of-color" effect, where the refraction of light changes depending on the size of the particles, producing different colors, creating the unique and beautiful colors of opal. With an elegant design, it's perfect for girls' gatherings and dates. ■The color of the photo may differ from the actual product depending on the shooting environment. Instant purchase OK. Thank you!