Juno diamond sells for $12.9M in Sotheby's New York auction

June 16 (UPI) -- The 100-plus carat Juno diamond was auctioned Thursday in New York by Sotheby's, bringing in over $12.9 million. The Earth Star, an orange-brown diamond of 111.59 carats, was expected to bring as much as $2.5 million.

The Juno diamond is a 101.41 carat pear-shaped internally flawless diamond named for the Roman goddess of light and fertility. According to Sotheby's, less than 2% of all gem diamonds are in the Juno diamond's category.

"The appearance of a 100-carat perfect diamond at auction is a noteworthy event. Only twelve D color, Flawless or Internally Flawless diamonds have sold at auction since 1990, and Sotheby's has had the privilege of selling seven of these important stones," said a post on Sotheby's web site.

"Just a handful of diamonds over 100 carats have ever been offered at auction," said Quig Bruning, head of jewelry for Sotheby's Americas. "The fact that we have two in one sale is rare beyond rare."

The Earth Star, a 111.59 carat deep orange-brown diamond, was on sale for the first time in four decades.

According to Barron's, the Earth Star is listed in the book "Famous Diamonds" by Lord Ian Balfour and was originally a 248.9-carat rough diamond found in in South Africa in 1967.

Both the Juno and Earth Star are approximately the size of a small egg, according to Sotheby's.