Collectors and jewelers snapped up more than 380 rare jewels at Christie's this week, making it the auction house's largest jewelry sales week in America in 15 years.

The top lot of the week was a 51.08-carat rectangular-cut D-color VVS1-clarity diamond set in an 18-karat white gold ring, which was sold at the Magnificent Jewels auction on Oct. 10 to a private European buyer for $3.15 million, or $61,700 per carat.

The next top lot of the week was a 22.63-carat marquise-cut D-color internally flawless diamond set in a platinum ring, which was sold at the Magnificent Jewels auction to a private American buyer for $1.75 million, or $77,420 per carat.

In addition to the Magnificent Jewels auction, Christie's hosted three other jewelry auctions this week: Magnificent Jewels from the Collection of Ellen Barkin on Oct.10, An Exceptional Collection of Art Nouveau Jewels on Oct. 11 and Van Cleef and Arpels: A Centennial Tribute Part I on Oct. 11.