Sotheby’s sold $54 million worth of jewelry at its New York auction on Tuesday as several pieces containing rare blue diamonds and gemstones yielded higher-than-expected prices.

An anonymous buyer spent $15.1 million, or $2.7 million per carat, on an emerald-cut, 5.69-carat, fancy vivid blue, VVS1-clarity diamond ring, beating its upper estimate of $15 million, the auctioneer said. Meanwhile, a pear-shaped, 2.05-carat, fancy intense blue, internally flawless diamond ring fetched $2.7 million, or $1.3 million per carat, in a sale to a member of the trade — well above its high estimate of $1.5 million.

Sapphire jewelry also attracted strong prices. A Van Cleef & Arpels bracelet containing 193.73 carats of the blue stones went to a private collector for $3.1 million, having drawn an estimate of up to $1.5 million. A sapphire-and-diamond necklace-bracelet combination by Harry Winston — with seven emerald-cut sapphires weighing a combined 123.13 carats — fetched $1.9 million, beating the expected price of up to $1.5 million.

The market continues to show its strength in colored stones, with today’s results driven by intense competition for important colored diamonds, sapphires and emeralds in particular,” Sotheby’s jewelry-division chair Gary Schuler said.

A 110.92-carat, L-color, VS1-clarity diamond — the largest round diamond in auction history — appeared on Sotheby’s list of unsold lots. The company did not immediately respond to a request for comment outside of New York working hours.