Known as an 80 Ducats coin, the item has been described by Stack's Bowers Galleries as “an exceptional Polish beauty."
The name of the buyer has not been disclosed.
The coin was minted at the Royal Mint in the Polish city of Bydgoszcz in 1621 to commemorate the nation's victory over the Turkish army at the Battle of Khotyn earlier that year.
It features on the front a portrait of Polish King Sigismund III Vasa, who ruled from 1587 to 1632. The king is depicted without a crown and with a shoulder plate adorned with a lion's head. The reverse side features the crowned coat-of-arms of the Republic of Poland of the time.
The Battle of Khotyn, or Chocim, was waged from September 2 to October 9, 1621 between a Polish-Lithuanian army and an invading Ottoman imperial army.
In 2018, Stack's Bowers Galleries, which is one of the world’s top rare coin auction firms, sold a 100 Ducats coin from the Bydgoszcz mint for USD 1.8 million.
(mk/gs)