A look at the ancient mythology, record-breaking finds and the surprising backstories of some of the world’s most famous diamonds…

1. Ancient Romans believed diamonds were poisonous and could ward off insanity.
Ancient Romans prized diamonds for their incredibly rarity and believed this rarity imbued diamonds with mystical powers. Romans would wear raw diamonds to protect themselves from succumbing to insanity and ward off ghosts and nightmares. It was also thought that diamonds were an antidote to any poison—but if diamonds were swallowed themselves, they became the world’s deadliest poison.

2. It is rumored that Catherine de Medici poisoned her enemies with diamond dust.
Catherine de Medici (1519-1589) was married to King Henry II of France. She was considered one of the most powerful women in 16th century Europe but was known for her ruthless politics aimed at keeping her family line on the throne. She was also looked at with great suspicion as her subjects believed she was affiliated with the occult.

Catherine’s hunger for power, coupled with her alleged familiarity with the dark arts, led people to believe she poisoned any political opponents with diamond dust. The rumors went so far as to claim the queen would test out her toxic potion of diamond dust on the sick and poor.

3. The first diamond engagement ring was recorded in 1477.
Throughout the 14th century, men typically gave their fiancé a simple ring engraved with both their names. But, in 1477, Austrian Archduke Maximilian set a new status symbol precedent for the European nobility when he proposed to Mary of Burgundy with a diamond engagement ring. The ring was set with thin, flat diamonds in the shape of an M.

4. The world’s largest diamond weighed 3,106 carats.
Later dubbed the “Cullinan Diamond,” this record-setting diamond was found at the Premier Mine in Pretoria, South Africa in 1905.

The diamond was cut by Joseph Asscher who examined the stone for six months before his first cut. When he did cut it, the diamond shattered precisely as Asscher wanted. However, Asscher himself fainted from the nervous energy and incredible pressure for handling the invaluable stone.

The Cullinan Diamond was ultimately divided up into nine large stones and 100 small stones. The largest of these, the “Star of Africa I,” weighs 530 carats and is classified as the largest-cut, fine quality colorless diamond in the world. The diamonds are worth an estimated $400 million USD.

5. The universe’s largest diamond is 10 billion trillion trillion carats.
In 2004, astronomers discovered a white dwarf star 50 light years away from Earth. This star is actually made of crystallized carbon, so it is effectively the universe’s largest diamond. It weighs 5 million trillion trillion pounds or 10 billion trillion trillion carats. The white dwarf was appropriately named Lucy after the Beatles song Lucy in the Sky with Diamonds.

6. The most expensive diamond in the world is a 59.60-carat pink diamond that sold for $71.2 million USD.
Although there are diamonds that are valued for more (like the Hope Diamond worth an estimated $350 million USD), these stones are considered invaluable and are unlikely to ever be put up for auction.

Therefore, the Pink Star diamond earns the title of the world’s most expensive diamond after being sold by Sotheby’s Hong Kong for $71.2 million USD in April 2017. The 59.60-carat oval mix-cut stone is considered the largest flawless fancy vivid pink diamond. The Pink Star was won by Hong Kong billionaire Dr. Henry Cheng Kar-Shun. Cheng Kar-shun bought the diamond to honor his late father and renamed the Pink Star the CTF Pink Star, after his family business Chow Tai Fook.

7. The “Uncle Sam” is the largest diamond ever found in the United States.
In 1924, W.O. Bassum found a 40.23 carat diamond in Murfreesboro, Arkansas. Dubbed the “Uncle Sam” diamond, it was worth nearly $1 million in today’s dollars. It remains the largest diamond ever found in the United States.

The site of this remarkable find sits atop a volcanic pipe, a sort of tube formed by ancient volcanic explosions, making it a hotbed for diamonds. Today, visitors to the Crater of Diamonds State Park can mine their own diamonds; it is the world’s only diamond site open to the public. And, if you get lucky and dig up the next “Uncle Sam” diamond, the park’s policy reads, “You find it. You keep it. No matter how valuable it is.” And since the park opened in 1906, over 75,000 diamonds have been discovered there.

8. The Hope Diamond is thought to be cursed.
The history of the Hope Diamond is fraught with death, theft, and deception.

The Hope Diamond was first acquired by a French diamond dealer named Jean Baptiste Tavernier in the 1600s in India. Tavernier went on to sell the diamond to King Louis XIV of France. The king then passed the diamond down the royal line where it became the position of the ill-fated and later beheaded Louis XVI. Following the French Revolution, the then-named French Blue diamond was put on display with the other seized crown jewels. But the stones were stolen in September 1792.

The stone mysteriously turned up 20 years later in 1812 in a small London diamond shop. It was then sold to the British King George IV. After the king’s death, it was sold to diamond collector Henry Philip Hope and earned its name The Hope Diamond. The Hope was an influential family at the time but later generations would largely squander the family’s wealth. Lord Francis Hope (Hope’s great-grandnephew) sold the Hope Diamond in 1901 to cover his crushing debt caused by his habitual horse betting and poor business decisions.

The New York jeweler Joseph Frankel’s Sons & Company purchased the diamond after putting up much of their business to raise the capital to afford the illustrious diamond. But, before they could make a return on their investment, the 1907 Banker’s Panic struck the US and any potential buyer vanished. The Hope Diamond then came into the possession of French jeweler Pierre Cartier.

It is believed Cartier exaggerated the mystery behind the Hope Diamond to entice American socialite Evelyn Walsh McLean to purchase the diamond. In a cruel twist of irony, Walsh McLean (who greatly admired the Hope Diamond and would parade it about at parties) experienced a series of personal tragedies: the death of her 10 year-old son in an automobile accident; her husband went insane; and her family’s business The Washington Post filed for bankruptcy.

Following this series of incredibly unfortunate events, all linked to the infamous Hope Diamond, it’s little wonder why some still believe the diamond is cursed.

9. To find one carat of diamonds, miners must sift through 250 tons of ore.
Only 20% of all the diamonds mined are of gem quality. The average size of a mined diamond is a mere .10 carats. In order to find a one carat stone, miners must dig up 200-250 tons of earth.

10. The world’s oldest diamond is 4.25 billion years old.
In 2007, scientists outside of Perth, Western Australia found the world’s oldest diamond trapped inside zircon crystals. While this may not have necessarily rocked the jewelry industry—the suspended diamonds are minuscule—it was a breakthrough for the scientists who are studying these diamonds to learn more about how the Earth formed. Already these grain-sized diamonds suggest that the Earth was cooler than scientists originally predicted.