A $150 million jewelry collection that belonged to a billionaire who made his fortune buying companies owned by Jews in Nazi Germany is set to go on auction at Christie's

• A jewelry collection once owned by a man who made a fortune buying up Jewish business in Nazi Germany will go to auction on May 3.
• The massive collection has more than 700 pieces and is valued at $150 million, according to The New York Times.

More than 700 jewels — valued at nearly $150 million and once owned by Helmut Horten, a man who made a fortune buying businesses from Jews who were forced to sell in Nazi Germany — are set to go on auction next week at Christie's.

The massive collection from the estate of Austrian heiress Heidi Horten, Helmut Horten's widow, will be one of the largest jewelry auctions in history, according to The New York Times.

Anthea Peers, president of Christie's Europe, Middle East, and Africa, said Christie's was aware of the "painful history" that the collection carries, and that the auction house had to grapple with it when deciding to host the items.

"We weighed that up against various factors," Peers told the paper, adding that the Helmut Horten Foundation is now "a key driver of philanthropic causes."

Peers said despite the ugly history, the collection is still one of the most beautifully curated that will ever come around in the jewelry world, The Times reported.

"This is a sale that will do an enormous amount for philanthropy," Peers told the paper. "That's important for the estate and for us."

Christie's did not immediately return Insider's request for comment on Sunday.

Stephanie Stephan, a Munich-based journalist whose father was on the board of a company that was forced to sell to Horten, published an affidavit that Horten threatened the men who owned her father's business with deportation to concentration camps if they resisted, according to The Times.

"My father rebelled against Horten from the very beginning because he knew that he had already forced several Jewish owners of department stores in Germany to sell their department stores for ridiculous sums," Stephan told the outlet. "He immediately dismissed my father. Horten made sure that my father was imprisoned several times and finally was expelled from the Netherlands."

A historian hired by Heidi Horten to investigate her husband's wealth said he has research that demonstrates Helmut Horten never finalized the purchase of Stephan's father's company. He said the affidavit was not "supported by records of that era," the outlet reported.

The collection's estimated $150 million value surpasses that of Elizabeth Taylor's jewelry collection, which sold for $137 million in 2011. One piece in the collection called the "Briolette of India," has a 90-carat diamond and has an estimated value of $7.8 million, according to The Times.