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April Birthstone Feature: ‘Splendor Of Diamonds’ Exhibit Assembles The Magnificent Seven

Back in the summer of 2003, the Smithsonian Institution in Washington, D.C., assembled an extraordinary collection of rare and valuable diamonds — one colorless and six colored — and called the exhibit “The Splendor of Diamonds.”

To celebrate April’s official birthstone, let's revisit what was billed as a once-in-a-lifetime opportunity to see the Magnificent Seven side by side.

The star-studded lineup included the 203.04-carat De Beers Millennium Star (colorless), 101.29-carat Allnatt (yellow), 59.60-carat Pink Star (formerly the Steinmetz Pink), 27.64-carat Heart of Eternity (blue), 5.54-carat Pumpkin Diamond (orange), 5.51-carat Ocean Dream (blue-green) and the 5.11-carat Moussaieff Red.

Millennium Star. Insured for $148 million, this D-color marvel is the world’s second-largest internally flawless pear-shaped diamond. Uncut, it was 777 carats. Using lasers, the Steinmetz Diamond Group took three years to perfect its final form. The diamond was introduced to the world in October 1999 as the centerpiece of the De Beers Millennium collection.

Allnatt. Rated fancy vivid yellow, the diamond’s brilliant color is the result of a chemical impurity, where trace nitrogen atoms replaced some of the crystal’s carbon atoms. The gem is named after its former British owner, Major Alfred Ernest Allnatt. The estimated value of the stone is at least $3 million.

Pink Star. This internally flawless gem is the largest known diamond to have been rated fancy vivid pink. Its value is $83.2 million. The Steinmetz Group took more than 20 months to cut the stone that is considered a mixed oval brilliant because it has a step-cut crown and brilliant-cut pavilion.

Heart of Eternity. Rated fancy vivid blue and valued at $16 million, this heart-shaped diamond gets its unique color from the presence of boron atoms trapped in the crystal structure. Blue diamonds account for less than 0.1% of the output of the Premier Diamond Mine in South Africa, the only place in the world with an appreciable production of blue diamonds.

The Pumpkin Diamond. This fancy vivid orange diamond was called the 5.54 Vivid Orange, but was renamed the Pumpkin Diamond by Harry Winston Inc.’s Ronald Winston, who purchased it on the day before Halloween in 1998. Valued at $3 million, the orange diamond was worn in a ring by film actress Halle Berry in 2002 when she received an Oscar for her role in Monster’s Ball.

The Ocean Dream. Known for its unusual fancy deep blue-green hue, this trillion-cut gem is one of the rarest diamonds in the world. The Gemological Institute of America concluded that the natural hue is the result of millions of years of exposure to the Earth’s natural radiation.

The Moussaieff Red. Rated fancy red by the GIA, this trillion-cut stone is the world’s largest red diamond. Cut and polished from a 13.9-carat crystal discovered in the 1990s by a Brazilian farmer, the diamond was originally called The Red Shield Diamond. It was renamed when Moussaieff Jewellers purchased the stone in 2002. It has an estimated value of $20 million.