3000 Francs CFA Elbphilharmonie

At 0.062 g, this is among the smallest gold coins in modern circulation programs — a format pioneered by the Austrian Mint and quickly adopted by various African franc-zone issuers working through intermediary minting agencies, typically European, with Chad holding nominal issuing authority. The Elbphilharmonie in Hamburg opened in January 2017 after a construction saga that ran thirteen years over schedule and nearly a billion euros over budget.