Currency money or book money, which are fiat money. Currency money Currency money is money in full circulation that takes its value from the precious metal it contains, that is, its market value is (almost) the value of the metal it contains (apart from the Seigniorage or the minters' profit), though this is always overcompensated for in coins and banknotes from a country undergoing debasement. Currency money is usually made of silver or gold, but in very rare cases plated metal and even copper may be used. Currency money is commodity money, as opposed to coins whose metal value is less than
Shall and will and "should" function as past tenses of "will" and "shall", their usage tends to correspond to that of the latter verbs ("would" is used analogously to "will", and "should" to "shall"). Thus "would" and "should" can be used with "future-in-the-past" meaning, to express what was expected to happen, or what in fact did happen, after some past time of reference. The use of "should" here (like that of "shall" as a plain future marker) is much less common and is generally confined to the first person. Examples: "Would" can also be used as the past equivalent of "will" in its