A narrow platinum Diamond eternity ringA narrow platinum half hoop eternity ring set with seventeen round brilliant cut white diamonds, each measuring approximately 1. 9mm in diameter, with an estimated total diamond weight of 0. 50 carats. The diamonds are of colour IK and clarity Si . The ring band spreads gracefully around the finger to 21mm, with a width just over 2mm, and a total weight of 3. 1 grams. Fully hallmarked for platinum (UK) with no date letter, the ring likely dates from