1Koh-i-Noor Diamond, a British Crown Jewel
When the Koh-i-noor Diamond arrived in the hands of the British royal family it weighed 186 carats (37 grams). Prince Albert carefully searched for a diamond cutter with a very good reputation and headed to the Netherlands where he gave the mission of cutting the diamond to a certain Mr. Cantor, who began the difficult task. It was then presented to Queen Victoria.
It became one of the Crown Jewels, and was last worn by the Queen Mother during her coronation as a mark of her becoming Empress of India. (Source 1 | Source 2)
2The Millennium, a Football-Sized Carved Sapphire
Designed by Italian artist Alessio Boschi, the Millennium Sapphire was conceived as a tribute to human genius and includes 134 subjects, including the faces of Beethoven, Michelangelo, Shakespeare, Albert Einstein, and Martin Luther King, Jr.
A consortium of investors led by Daniel McKinney owns the Millennium Sapphire. Over the past 15 years, the impressive carved sapphire has been on public display only twice — in 2002 during the Academy Awards and two years later for the maiden voyage of the Sapphire Princess cruise liner.
The 28 cm (11 inch) Millennium Sapphire was unearthed in Madagascar in 1995. It weighed about 90,000 carats in its rough state and lost about a third of its mass during the carving process, which took two years and was completed in 2000. (Source)
3Dom Pedro, the World's Biggest Aquamarine Gem
Mined from a Brazilian pegmatite in the 1980s, and named for Brazil's first two emperors, the Dom Pedro Aquamarine occupies a distinguished place at the National Museum of Natural History, part of the Smithsonian Institution.
The obelisk-shaped, blue-green gem, which was designed by famed German gem cutter Bernd Munsteiner, known as the "father of the fantasy cut," stands 14 inches (35.5 centimeters) tall and weighs 10,363 carats, or 4.6 pounds (two kilograms). (Source)
4World's Largest Pearl
The stone, formed mostly of fluorite mineral, glows green in the dark. Its finders took three years to grind the raw gem down to its pearl shape. (Source)
5The Graff Pink, the World's Most Expensive Pink Diamond
He is also Britain's richest living art buyer, splashing $24.1m in New York on two of Warhol's best works - "Elvis" and "Campbell's Soup Can." Laurence Graff also owns five luxurious homes in England, France, Switzerland, and New York, as well as a private Mediterranean yacht. He also owns his own diamond mine outside of Johannesburg, along with half a dozen properties in Mayfair.
The amazing “potentially flawless” pink diamond has set a new record with the auction price stunning the staff at Sotheby's. The auction was laced with gasps as the bids kept coming in. Pink Diamonds UK had never seen such excitement. Britain's 36th richest man and Diamond geezer eventually paid £29 million ($45 million), the most ever paid for a jewel. (Source)
6Ethereal Carolina Divine, the Largest Cut Paraiba Tourmaline
Paraiba tourmaline is one of the rarest jewelry gems in the world, favored by connoisseur collectors and showcased by elite jewelers worldwide. There is one Paraiba tourmaline (named for the Brazilian region where the vast majority are found, including Boucher's) mined for every 10,000 diamonds, and Boucher pointed out that only a total of 50 kilograms of the gem have been recovered to date. (Source)
7Massive Uncut 478-Carat Diamond
8World's Most Expensive Gemstone Per Carat Sold at Auction
The blessed buyer is Moussaieff Jewelers based in London, who was glad to purchase this diamond from a private Asian collector, as it would be an addition to their rare collection of precious jewels. Blue diamonds are known for captivating the filthy rich gentry with glittering dark charisma. True, it is not the largest stone, but its revered cut and "vibrant blue" hue is what justifies its bulky price, which is almost ten times the per-carat price of regular white diamonds. (Source 1 | Source 2)
9Bahia Emerald, the World's Largest
After being moved from Brazil to the United States, various attempts were made to sell it without success; there were conflicting claims of ownership. Eventually, the emerald was seized from a gem dealer in Las Vegas and taken into the custody of the Los Angeles Sheriff's Department. (Source)
10The Moussaieff Red, the Most Famous Red Diamond