Vintage 18k white gold lady's ring with a fine Australian opal pear-shaped cabochon set in platinum prongs. The opal weighs approximately 6.21ct, and measures 11.3mm x 20.4mm x 4.75mm. The mounting has an inside hallmark of "A&C", with finger size at 4.75 (resizing is possible) and a total weight of 4.8g. The height off the finger is 9mm, and the shank width is 1.8mm where it joins the cabochon and tapers down to 1.5mm at the bottom. The inner thickness tapers from 1.4mm to 1mm. The ring is in good condition with minor wear.