The Eliasberg 1913 Liberty Head nickel, one of only five ever produced, is now one of the five most valuable coins ever sold at auction and holds the title of “most valuable non-precious metal coin.”

Only two more of this particular coin are in private hands. The others are in museums, including the Smithsonian.

The nickel in question comes from the family of Dr. William Morton-Smith, whose passion for coin collecting started when he was inspecting a desk passed down to him from his family. He discovered a hidden compartment, which held a coin collection that included colonial coins, a set of Proof Liberty Head nickels and more that had belonged to his great grandfather.

That set him on the path of numismatics, where he began gathering rare coins, including the Eliasberg 1913 Liberty Head nickel.

The $4.5 million is well beyond the $2 million a collector paid for a dime two years ago. It’s also well below the $52 million in Bitcoin U.S. Marshals auctioned off earlier this year, though some would argue the nickel is more likely to accrue in value.

The buyer’s name was not disclosed.