Viking coinage was used during the Viking Age of northern Europe. Prior to the usage and minting of coins, the Viking economy was predominantly a bullion economy, where the weight and size of a particular metal is used as a method of evaluating value, as opposed to the value being determined by the specific type of coin. By the ninth century, the Viking raids brought them into contact with cultures well familiarised with the use of coins in economies of Europe, hence influencing the Vikings own production of coins.