A copper mug traditionally serves a classic Moscow Mule.
The Moscow Mule is generally made with vodka, ginger beer and lime juice, then served in a copper mug. The vessel became one of the drink’s most recognizable features and helped distinguish it in American bar culture. The mug also conducts temperature efficiently, making the drink feel particularly cold when it is served over ice.
Despite its name, the cocktail was created in the United States rather than Moscow. It is commonly credited to John G. Martin and Jack Morgan in the early 1940s. Martin was promoting vodka, while Morgan owned the Cock ’n’ Bull restaurant and had an interest in ginger beer. Their collaboration helped popularize the combination.
Modern service sometimes uses stainless steel or other materials, especially where copper safety rules apply. The traditional presentation, however, is the copper mug. The name refers to the drink’s association with vodka and its distinctive presentation, not to a Russian origin.