What is A.S.W. (Actual Silver Weight)?

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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 Troy ounce of silver. For example, a coin that has an ASW equal to 0.18084 means that the coin has 0.18084 of a Troy ounce of pure silver in it.

It is important to know this number and to know the current price of silver. Armed with this information you can make wise coin buying and selling decisions.

For example, if silver is rising rapidly the value of the silver in the coin could exceed the numismatic value that is listed coin value guides. Conversely, if the value of silver is falling, the coin may be worth more to a coin collector then to a scrap metal dealer who will melt it.

How To Calculate the ASW of a Coin

Begin by taking the weight in grams and divide it by the total number of grams in a Troy ounce (31.1034768), and then multiply the result by the fineness. For example, if a coin weighs 6.25 grams and is made out of 90% fine silver, then the calculation would be: 6.25 / 31.1034768 * 0.900 = 0.18084 ASW (truncate, or cut off, at the 5th decimal place, if necessary.)

How to Determine the Silver Value in a Coin 

Multiply the ASW by the spot price of silver. For example, if the spot price is $18.35 a Troy ounce, take 0.18084 x 18.35 = 3.318414, or about $3.32 worth of silver.

Example ASW for U.S. Coins:

  • Morgan Dollar - Total Weight: 26.730 grams of 90% silver ASW=0.7734 Troy Ounces  
  • Standing Liberty Quarter - Total Weight: 6.250 grams of 90% silver ASW=0.1808 Troy Ounces
  • Kennedy Half Dollar - These coins were minted in three different compositions
    YearSilverActual WeightASW
    1964 & Silver Proof 1992 - Date 90% 12.50 g. 0.3617 Troy Ounces 
    1965 - 1970 & 1976 Collector Coins 40% 11.50 g. 0.1479 Troy Ounces
    1971 - Date None 11.34 g. 0.0000 Troy Ounces

    Selling Your Coins for Their Silver Value

    Coins that have very heavy wear on them, are damaged and/or are not great rarities are usually worth more for their silver content than their collectibility as numismatic items. You can take these coins to your local coin dealer or scrap metal recycling dealer to sell them. Some coin dealers will pay a certain dollar value per face value of coins that you're turning it. In other words, if silver is around $18 per Troy ounce they may pay $13 for every silver dollar, $6.50 for every half dollar, etc. Other dealers may put your coins on a scale in pay you according to the weight of the silver that is contained in the coins.

    Edited by: James Bucki