or ALLAY, properly signifies a proportion of a baser metal mixed with a finer one. The alloy of gold is estimated by carats, that of silver by pennyweights. In different nations different proportions of alloy are used; whence their moneys are said to be of different degrees of fineness or baseness, and are valued accordingly in foreign exchanges. The chief reasons alleged for the alloying of coin are: 1. the mixture of the metals, which, when smelted from the mine, are not perfectly pure; 2. the saving of the expense it must otherwise cost if they were to be refined; 3. the necessity of rendering them harder, by mixing some parts of other metals with them, to prevent the diminution of weight by wearing in passing from hand to hand; 4. the melting of foreign gold or coin which is alloyed; 5. the charges of coinage, which must be made good by the profit arising from the money coined; 6. and lastly, the duty belonging to the sovereign, on account of the power he has to cause money to be coined in his dominions.