When Prince William and Kate Middleton wed back in 2011, she became one of the most famous women in the world. As the wife of the future king, Kate quickly inherited plenty of popularity, a royal title, and also a number of expensive jewelry pieces. Through the years, the Princess of Wales has accumulated a hefty jewelry collection worth more money than most will ever see in their lifetime.

The princess’ most expensive necklace originally belonged to Queen Elizabeth II, and it’s worth an estimated $80 million.

Kate Middleton’s most expensive necklace has 13 massive diamonds

William and Kate met in college, and although they were friends first, they always shared something special. The prince and princess dated through their university years and into their mid-twenties, and William finally popped the question in 2010, more than eight years after he and Kate first met.

Once Kate and William wed in 2011, she became an official member of the royal family, and the jewelry collection began. Kate eventually inherited her most expensive piece of all, a necklace that was originally gifted to Queen Elizabeth II back in 1947 as a gift from the Nizam of Hyderabad, Osman Ali Khan. He gifted the queen the necklace as a wedding present.

“The Nizam of Hyderabad necklace is a truly delicate and extravagant piece. It features 13 emerald-cut diamonds and a pear-shaped center diamond and is rumored to be the royal family’s most expensive piece, estimated at around £66 million,” Stephanie Tyler of Purely Diamonds said of the piece, according to Express. That translates to about $80 million.

The necklace, which was originally made by Cartier in 1935, first appeared on the Princess of Wales back in 2014 when she wore it to an art gallery event.

Kate Middleton’s jewelry collection features a number of high-end pieces

None of Kate’s other jewelry even comes close to the price of the necklace, but she certainly does own plenty of expensive jewels. Her Cartier halo tiara is worth more than $1 million, while her engagement ring from Prince William, which was previously owned by Princess Diana, is worth more than $350,000.

Kate will presumably pass some of her jewelry down to her children once they come of age. Princess Charlotte will almost certainly inherit a number of pricey pieces, and Princes George and Louis could end up with some jewelry in their families, depending on who they marry. Kate’s jewelry collection will likely only continue to grow once she officially takes the throne with William.