Definition: The ASW (sometimes written as a.s.w. or asw) is the Actual Silver Weight of a coin. The ASW is expressed as a decimal value of one full ounce of silver, so .18084 asw means that the coin has 0.18084 of an ounce of pure silver in it. Here are two examples using a pre-1965 90% silver U.S. Quarter Dollar, with an asw of .18084, a total weight of 6.25 grams, and a fineness of .900:
To determine the coin's actual silver value, multiply the asw by the spot price (for example, if the spot price is $18.35 an ounce, take .18084 x 18.35 = 3.318414, or about $3.32 worth of silver.)
To calculate the actual asw of a coin, take the weight in grams and divide it by the total number of grams in an ounce (31.1034768), and then multiply by the fineness. For example, 6.25 / 31.1034768 * .900 = .18084 asw (truncate, or cut off, at the 5th decimal place, if necessary.)
To determine the coin's actual silver value, multiply the asw by the spot price (for example, if the spot price is $18.35 an ounce, take .18084 x 18.35 = 3.318414, or about $3.32 worth of silver.)
To calculate the actual asw of a coin, take the weight in grams and divide it by the total number of grams in an ounce (31.1034768), and then multiply by the fineness. For example, 6.25 / 31.1034768 * .900 = .18084 asw (truncate, or cut off, at the 5th decimal place, if necessary.)
Examples:
A U.S. Morgan Dollar has .77344 asw, or a little more than 3/4 of an ounce of pure silver in it.