Diamonds are formed deep within the Earth about 100 miles or so below the surface in the upper mantle.
Diamonds are quite old. At least hundreds of millions of years old, but in most cases billions of years old, anywhere from one to three billion years old, a time when the earth was probably hotter than it is today and so conditions were perhaps more appropriate for diamond growth. You can read more about diamonds at the Smithsonian. Lately diamonds have been hot so to speak.
The most outstanding ones for me are the diamonds with color.
The Red Diamond
Vivid Oppenheimer Blue Diamond
According to Christie’s website, this 14.62 ct. diamond called the Oppenheimer Blue, is the largest fancy vivid blue diamond ever offered for auction.
“The Oppenheimer Blue can only be described as one of the rarest gems in the world,” said Curiel. “It is the gem of gems.”Those details are part of what makes the gem so rare. Rahul Kadakia, Christie’s head of jewelry, told CNBC that less than 2 percent of the diamonds found in the world are blue, and only 10 percent of them are larger than a carat.
“Blue diamonds range from a very faint baby blue, a powder blue, to a dark, dark-indigo blue [that’s] almost too dark,” Kadakia said. “Vivid is the purest, most open, almost a happy blue color.”
Indigo Blue Diamond
Vivid Orange Diamond
The Graff Vivid Yellow Diamond
Dresden Green Diamond
The most famous natural-color green diamond is considered by many to be the Dresden Green . GIA. The green color in a diamond is the result of exposure to radiation. The source of the radiation can be naturally occurring or performed in a laboratory. Natural radiation is the result of the diamond being exposed to radioactive uranium from rocks near the earth’s surface.
The Argyle Violet Diamond
Rio Tinto has recovered its largest ever violet diamond from its Argyle mine in Western Australia.
Unique Pink Diamond
The “Unique Pink,” the largest Fancy Vivid pink pear-shaped diamond ever offered at auction, came to Sotheby’s New Bond street galleries in London. According to Ehud Laniado, the head of Cora International “People are bidding very high prices, which means that they don’t see diamonds as just an expense,” he says. “They are starting to be seen as an asset, more than something you just use in jewelry. In 11 years, pink stones have gone up by 350 percent. Compare that to gold, which only went up 150 percent.” With this said the unique point is made for the pink.