Tank ring in pink gold, platinum, diamonds and rubies

A Tank ring in 750/000 pink gold and 950/000 platinum in a rectangular shape with gadroons centered with a half-cut round diamond of approximately 1 carat framed by old-cut diamonds and calibrated rubies. Length: 21mm Width: 20mm Height: 7mm Weight: 11.5 grams Diamond weight: approximately 1 carat Finger size: 51