8.# Metal money without or with coinage#.  In antiquity the metals were used as money in bulk; that is, the amount was weighed at each transaction and the quality was tested whenever there was doubt.[4] In countries industrially backward, payments are still made in this manner.  For some time after the discovery of gold in California, gold dust was roughly measured out on the thumb-nail.  In shipments of gold to-day by bankers to settle international balances, metal may be in the form of bars that bear the mark of some well-known banking house.  In all of the cases of this kind the gold is money in fact, but not by virtue of any act of government.  The metal is simply a valuable good, the receiver of which values it according to its weight and fineness.  This is true even when the government mint, for a small charge, tests and stamps the bars at the request of citizens.

Very early it became the practice of governments to shape and stamp pieces of metal to be used as money, so as to indicate their weight and fineness.  The act of shaping and marking metal for this purpose is called coinage.[5] The coinage by government had notable advantages in giving to the monetary units uniformity of size, fineness, and value, with the stamp that was readily recognized.  But in its simplest form coinage in no way changed the value of the money, and any other mark equally plain put upon it would have served equally well, if only it had carried with it equal assurance of the quality and weight of the metal.

9. #Technical features of coinage#.  For each kind of metal money there is an established ratio of fineness for the more precious material, which is mixed with baser metals used as alloys.  In the United States all gold and silver coins are made nine-tenths fine; in Great Britain, eleven-twelfths.  The established weight of the gold dollar in the United States is 25.8 grains of standard gold which contain 23.22 grains of fine gold.  The limit of tolerance is the variation either above or below the standard weight or fineness that a coin is allowed to have when it leaves the mint.  This is different for each of the principal coins, being about one-fifth of one per cent on a gold eagle.  The par of exchange between standard coins of different countries is the expression of the ratio of fine metal in them.  Thus the par of exchange between the American dollar and the English sovereign (the “pound”) is 4.866; that is, that number of dollars contains the same amount of fine gold as an English gold sovereign.  The embossed design is merely to make the coins easily recognizable and difficult to counterfeit; and milled or lettered edges are to prevent clipping and otherwise abstracting metal from the coins.