Rare jewelry that once belonged to Marie Antoinette and hasn't been seen in public for 200 years will be heading to the auction block this fall, according to The Adventurine.

A diamond parure (jewelry set), three-strand pearl necklace, and other gems that once adorned the last queen of France will be sold on November 12 in Geneva, Switzerland, as part of Sotheby's "Royal Jewels from the Bourbon-Parma Family" auction. The family in question is related by blood to some of Europe's most important rulers, including former kings of France and Spain and emperors of Austria.

Courtesy of Sotheby's

Although Marie Antoinette was known for her opulent fashion choices, her jewels have scarcely been seen since the French Revolution, The Adventurine reports. The Smithsonian owns a pair of earrings that are believed to contain diamonds from the queen's collection, and a diamond necklace that appeared at a Christie's auction in 1971 "hasn't been seen since." The jewelry magazine notes that many of Marie Antoinette's jewels were dismantled, but a few—like the ones featured in this latest collection—managed to survive.

Courtesy of Sotheby's

According to Sotheby's, Marie Antoinette placed all her jewels in a wooden chest in March 1791 and shipped them off to her nephew, the Austrian Emperor, for safekeeping [PDF]. That following year, the royal family was imprisoned, and in 1793 Marie Antoinette and King Louis XVII were executed by guillotine. Their only surviving child, Marie Thérèse de France, retrieved the jewels and later passed them along to her niece, since she had no children of her own. They ultimately ended up with Robert I, the last ruling Duke of Parma in Italy.

The most valuable piece, a pearl pendant featuring a bow made of diamonds, is expected to fetch between $1 million and $2 million, according to the auction house's estimates. In the late 18th century, pearls were just as coveted as diamonds because of their rarity. Marie Antoinette, of course, wore them often.

Courtesy of Sotheby's

"It is one of the most important royal jewelry collections ever to appear on the market and each and every jewel is absolutely imbued with history," Daniela Mascetti, of Sotheby's European jewelry division, said in a statement.

[h/t The Adventurine]