New York officials have returned more than $20 million worth of ancient artifacts to Greece, including an “extraordinarily rare” gold coin commemorating the assassination of Julius Caesar which set auction records in 2020 as the most expensive coin ever sold, Report informs via CNN.

The repatriation ceremony took place on Tuesday at the Greek Consulate in New York City and included 29 Hellenic antiquities dating back as early as 5,000 BCE, according to a news release from the office of Manhattan District Attorney Alvin Bragg. All of the antiquities were seized in connection with trafficking and smuggling investigations; New York Homeland Security Investigations special agent Ivan J. Arvelo said in a statement that Grecian artifacts are “especially susceptible” to trafficking because ancient Greece has “long (been) acknowledged as the cradle of Western Civilization.”

Among the repatriated items is the “Eid Mar Coin,” which sold to an anonymous bidder in the United States for £2.7 million ($3.5 million) through the Roma Numismatics auction house in London. But the coin had been smuggled into the UK after previously being offered for sale in Germany with no declared provenance, according to the release. The Manhattan DA office seized the coin in February.

In March, multiple outlets reported that an auction house executive was arrested in New York in January in connection with a US Department of Homeland Security investigation related to the sale of two coins, including the Eid Mar, and their provenance.

Only one of three of its kind still known to exist, the coin features a portrait of the Roman politician Marcus Junius Brutus, who famously helped orchestrate Caesar’s assassination in 44 BCE, as well as depictions of the daggers used to kill him. It is inscribed with the phrase “Eid Mar” — or the “Ides of March” — which references the date of Caesar’s death. The coin was minted two years later, in 42 BCE, in order to pay Brutus’ troops after he and his co-conspirators had been forced to flee Rome in the aftermath of the killing.

Other artifacts include the Bronze Calyx Krater, from 350 BCE, a vessel which formerly contained human remains, according to the Manhattan DA’s office, and a group of human and animal figures from 5,000-3,500 BCE which were sold to private New York collectors in the early 1980s. Called the “Neolithic Family Group,” the figures are worth $3 million, and were on loan to the Metropolitan Museum of Art in New York until their seizure in March.