Apothecaries' system between actual and nominal weight. In the 19th century, most European countries or cities still had at least a "commercial" or "civil" system (such as the English avoirdupois system) for general trading, and a second system (such as the troy system) for precious metals such as gold and silver. The system for precious metals was usually divided in a different way from the commercial system, often using special units such as the carat. More significantly, it was often based on different weight standards. The apothecaries' system often used the same ounces as the precious metals system, although even then the
Coinage metals However, the author defended his choices: The British Royal Mint's rhodium token "is only rhodium-plated", and the Pobjoy Mint's iridium coin "does not exist (possible confusion with palladium?)." Curiously, chromium and manganese were not mentioned, even though both elements had been used in common circulation coins (Canada wartime V nickels and US wartime Jefferson nickels, respectively) long before the time of the article's publication. Coinage metals The coinage metals comprise, at a minimum, those metallic chemical elements which have historically been used as components in alloys used to mint coins. The term is not perfectly defined, however, since a number