The Pink Star is the most valuable gemstone in history. The Pink Star is the most expensive precious gemstone ever auctioned, with a price tag of more than $71 million. The astronomically priced diamond weighed 59.60 carats, making it the largest internally perfect diamond ever graded by the Gemological Institute of America (GIA).

Sotheby's auction house had a long history of selling valuable jewels, and the Pink Star was no exception. "[There is] extraordinary demand for the finest in colored diamonds," one Sotheby's salesperson said.

De Beers Mining Company mined this extremely valuable gemstone in 1999. Before being cut down to the Pink Star's magnificent 59.60 carats, the original, uncut diamond weighed in at 132.5 carats.

The Pink Star took De Beers two years to cut and polish.

Price: $71.2 million

Year Sold: 2017

Number of Carats: 59.60

Interesting Fact: The largest diamond of its kind graded by the GIA

The Oppenheimer Blue is known as the second on the list of most expensive gemstones and the largest diamond of its kind ever sold at auction. In 2016, a final bid of $58 million was placed on the magnificent 14.62-carat diamond.

Surprisingly, the bidding for this rock took more than 20 minutes. "It felt that for those 20 minutes the diamond belonged to everyone as they celebrated each bid the stone received," someone in the room remarked during the auction.

The Oppenheimer Blue was named after Sir Philip Oppenheimer, one of the company's previous owners. Sir Philip was a member of the De Beers Mining Company family, which also controlled the Millenium series.

Price: $58 million

Year Sold: 2016

Number of Carats: 14.62

Interesting Fact: This was the largest diamond of its kind to appear at auction

The Pink Legacy is a beautiful 18.96-carat diamond held by Harry Winston, a colored gem chevalier (a luxury jewelry company). When Christie's auction house put the ultra-expensive rock up for sale in November 2018, it fetched more than $50 million.

Despite how much money the corporation spent on the Pink Legacy, Harry Winston was said to be "open to proposals" in early 2021.

The Pink Legacy, like the other gemstones on this list, was placed in a ring.

The Pink Legacy diamond is described as "fancy vibrant pink." Surprisingly, in the world of jewelry, the title is quite technical. The term "fancy" refers to the diamond's unique traits, such as its deep color.

Price: $50.4 million

Year Sold: 2018

Number of Carats: 18.96

Interesting Fact: Part of the rare “fancy” diamond variety

What about Joseph Lau? That millionaire who bought his daughter a $28 million diamond? That didn't seem to satisfy the 7-year-old. Joseph Lau purchased a $48.4 million, a 12.03-carat stone called Blue Moon just one day after his multimillion-dollar purchase. In honor of his daughter, Joseph named it The Blue Moon of Josephine.

Lau's spokeswoman formally confirmed these lavish purchases, according to a newspaper.

By any measure, this gemstone is pricey, yet Joseph Lau could easily afford it. According to Forbes, Lau is worth around $13.5 billion, which is nearly $1.50 for every person on the earth.

Price: $48.4 million

Year Sold: 2015

Number of Carats: 12.03

Interesting Fact: Purchased for a 7-year-old

Harry Winston, a jeweler who collected valuable stones, was the first to own this gem. For over 60 years, Harry maintained this gem in his personal collection.

Laurence Graff eventually bought the diamond for $46 million in 2010. Undoubtedly, the Graff Pink Diamond is one of the most expensive gemstones in the world. Graff is the King of Bling, a diamond collector.

Although the Graff Pink Diamond is extraordinarily pricey, some people appear to believe that its beauty is worth it. "Its beauty has plagued me since the very first time I set eyes on it some years ago," one devotee said.

Despite the fact that many people assumed this diamond was flawless, Laurence Graff discovered "25 natural defects." Graff reportedly employed cutting-edge technology to correct the defects while maintaining the diamond's original form.

Price: $46 million

Year Sold: 2010

Number of Carats: 24.78

Interesting Fact: Kept in a private collection for 60 years

10-carat stones are generally pricey, but they don't get this pricey very frequently. The De Beers Millennium series consisted of 12 diamonds designed to commemorate the year 2000. This particular diamond was the fourth in the set.

This magnificent diamond is the most costly jewel ever sold at auction in Asia, despite not being the most valuable gemstone ever sold. The previous record was set in late 2013 when a 118.28-carat D flawless diamond sold for $30.6 million.

Despite the fact that the buyer was unknown, one-story speculates that this diamond piqued the curiosity of Joseph Lau, a billionaire who bought a 16.08-carat diamond for his daughter in 2015. That $28.5 million diamond is incredible.

Price: $31.8 million

Year Sold: 2016

Number of Carats: 10.10

Interesting Fact: The most expensive jewel sold at auction in Asia

This is yet another expensive gemstone sold by Sotheby’s. This time it’s a rare ruby weighing over 25 carats. Like other gems on this list, this rare ruby is complemented by diamonds.

Interestingly, rubies of this size are very hard to find. This is reportedly due to the geographic conditions required for rubies to develop.

Although some might just call it red, this ruby is typically referred to as “pigeon blood red” by gem experts. The stone gets that coloring from “well-balanced” trace elements. These elements include chromium, a hard metal that actually appears steel-gray on its own.

The diamonds on either side of this ruby are marked by Cartier, a luxury jewelry maker.

Price: 28,250,000 CHF (about $30.5 million USD)

Year Sold: Believed to be around 2015

Number of Carats: 25.596

Interesting Fact: Described as “pigeon blood red”

Little is known about this magnificent diamond, but we do know that it sold for $13.8 million at a Sotheby's auction. The spectacular diamond, which weighs over 88 carats and sold for more than $12.8 million, outperformed its projected sale price. And it became one of the most expensive gemstones ever sold.

This diamond is unmounted, which means it hasn't been set in a ring or other piece of wearable jewelry. A "loose diamond" is another term for this.

Although Sotheby's did not reveal who bought the diamond, it appears that the buyer was from Hong Kong.

The cut of this diamond is oval. This is a contemporary take on the more classic pear shape and round brilliant cutting methods.

Price: 107,993,000 HKD (about $13.8 million USD)

Year Sold: Unknown

Number of Carats: 88.22

Interesting Fact: N/A

The Jewel of Kashmir is a $6.7 million sapphire surrounded by pear-shaped diamonds. The incredibly expensive gem was sold in 2015 by Sotheby’s auction house. According to Sotheby’s, the gem is completely natural and reportedly comes from Kashmir, a region near India.

Interestingly, sapphires from Kashmir are incredibly rare. Important sapphire mines in the region were depleted by the late 1800s, so it’s become essentially impossible to unearth more of these precious stones in the area.

Kashmir sapphires are often praised for their beautifully rich color. Experts call this stone “cornflower blue,” but all Kashmir sapphires are noteworthy for their ability to maintain perfect coloring under any light source.

Price: 52,280,000 HKD (about $6.7 million USD)

Year Sold: 2015

Number of Carats: 27.68

Interesting Fact: Stones of this kind are very rare due to depleted mines

In 2015, a rare gemstone sold for about $1.5 million. That astronomical price was reduced to around $30,000 per carat.

Henry Philip Hope, a banker, was the owner of the Hope Spinel. Before his death in 1839, Henry owned around 700 gems. Before 2015, a portion of Henry's collection had not been sold in 98 years.

The Hope Spinel was placed among rose-cut diamond claws and framed by larger brilliant-cut diamonds totaling 6.5 carats as if that wasn't enough.

The auction house Bonhams auctioned this gemstone. Bonhams sold an 18-carat stone set in an art deco-inspired ring for more than $70,000 in 2012, prior to the Hope Spinel.

Price: $1.47 million

Year Sold: 2015

Number of Carats: 50.13

Interesting Fact: Set among other precious stones