BOSTON — Bringing more than five times its low estimate ($60/80,000), a cushion-cut 4.74-carat sapphire ring with old European-cut diamonds topped Skinner’s May 21 jewelry sale when it sold for $339,000. The ring was accompanied by two documents attesting that the sapphire originated in Kashmir and had no evidence of heating. It had been passed down in the same family for more than 100 years. See a future issue for complete sale review.