A distinction must be drawn between full value bullion trade coins, that were used in ordinary peacetime trade on the one hand, and on the other hand debased coins, that were usually made with the intention to deceive. Such debased "trade coins" were occasionally minted during times of war, e.g. the Prussian ephraimiten, silver-clad copper coins minted during the Seven Years' War. If these were ever accepted or approved as legal tender, they would be valued far below the regular coins, their value being calculated according to a specified formula.