A man holds a gold coin up to the camera
Vicken Yegparian, vice president of numismatics, Stack's Bowers Galleries, holds a golden coin that is part of L. E. Bruun's collection.
  • A legendary Danish coin collection will go up for sale later this year after 100 years.
  • The auction house handling the sale says the collection is worth $72 million.
  • The tycoon who compiled the collection stipulated it could not be sold until 100 years after his death.

One of the most valuable privately-owned coin collections is headed to auction later this year after spending more than a century shrouded in secrecy.

The collection once belonged to Danish businessman and butter tycoon Lars Emil Bruun, who spent decades compiling the nearly 20,000 coins, bank notes, and medals that comprise the set. For over a century, the collection has been kept out of the public eye due to a stipulation in Bruun's will that forbade the coins from being sold until a century after his death in 1923 at 71.

Emotionally impacted by the devastation of World War I, Bruun determined the collection should be kept as backup reserves for Denmark should a second war ravage Europe, The Washington Post reported.

The collection in total is estimated to be worth up to $72 million, making it the most valuable coin collection ever to go to sale, according to Stack's Bowers, the New York rare coin dealer and auction house overseeing the sale.

The proceeds from the sales will go to Bruun's heirs. At least one of Bruun's descendants was involved in an effort to negotiate a sale of the coins to a museum in Denmark before the required century of waiting was up, but Danish authorities ultimately shut down the sale, citing the businessman's will, The Post reported.

Bruun began collecting coins as a boy in the 1850s and 1860s, long before he made millions exporting butter to England and other countries, according to The Associated Press. His vast wealth allowed him to continue pursuing his coin hobby in later years. Bruun initially kept his collection at Frederiksborg Castle, the former royal residence located north of Copenhagen, but it was later moved to the Danish Central Bank, per The Post.

Since 2011, however, the collection has lived in a secret location of which even coin enthusiasts are in the dark.

"When I first heard about the collection, I was in disbelief," Vicken Yegparian, vice president of numismatics at Stack's Bowers Galleries, told The AP, calling the collection "the best open secret ever."

The National Museum of Denmark got first dibs on the collection, ultimately snagging seven rare coins, including six gold and one silver, that were minted for $1.1 million, according to the outlet.

"We chose coins that were unique. They are described in literature as the only existing specimen of this kind," Helle Horsnaes, senior researcher at Denmark's National Museum, told The AP.

The sales are set to begin this fall and could take anywhere from three to five years, according to Stack's Bowers.

Some pieces in the collection could go for as cheap as $50, while others could fetch $1 million, Yegparian told The AP.

Read the original article on Business Insider