Platinum and Diamond Solitaire. Photo courtesy Skinner. Platinum and Diamond Solitaire, prong-set with an old mine-brilliant-cut diamond measuring approx. 8.89 x 8.18 x 5.58 mm, and weighing 3.04 cts., within a pave-set diamond mount, size 6. Estimate...

Platinum and Diamond Solitaire. Photo courtesy Skinner. Platinum and Diamond Solitaire, set with an emerald-cut diamond measuring approx. 11.60 x 10.09 x 6.39 mm, and weighing 6.31 cts., flanked by tapered baguettes, size 4 1/2. Estimate $60,000-80,000...

Platinum and Diamond Solitaire. Photo courtesy Skinner. Platinum and Diamond Solitaire, prong-set with a pear-shape diamond measuring approx. 19.00 x 12.40 x 7.10 mm, and weighing 10.02 cts., flanked by tapered baguettes, (hinged shank). Estimate $70,000-90,000...