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Silver weight matters

As the prices of precious metals escalate, the accuracy of weight and purity can make a difference.

Weight and purity matters when gold and silver are on the line.

Weight and purity matters when gold and silver are on the line.

For example, an exact-weight 1,000 troy ounce silver bar of .999 purity can have as much as one ounce of other components. In contrast, the same weight of bar fabricated to .9999 purity as required to be eligible for trade on the London Bullion Market, is limited to 0.1 ounce of non-silver content.

At $10 per ounce silver price, the difference between these two purities could vary as much as $9. If the price of silver were at $100, however, the potential variance could be as high as $90 per bar.

A tube of 10 pieces of early-year 1 troy ounce Gold Maple Leaf coins was struck to .999 purity. Later the Royal Canadian Mint adopted the stricter standard of .9999 purity. For the tube, that could make a difference of as much as 0.009 of an ounce. At $1,200 gold spot, that could make a difference of more than $10 per tube.

As a percentage of total value, these fractions of purity don’t really make that much difference. Currently manufactured coins and ingots are struck under such strong quality controls that every piece contains the stated weight or slightly more (as opposed to the pieces having an average precious metal content as stated, meaning some could be slightly light).

Where net metal content could become more significant is with older coins that endured extensive circulation. In general, most gold coins did not circulate widely back in the days when gold coins were actually being spent. Because of this, there are almost no concerns about lost weight.

However, silver coinage can be a different story. U.S. 90 percent silver coins circulated for decades until the last issues were struck dated 1964 (some of which were actually minted in 1965 and 1966). In uncirculated condition, $1,000 face value of U.S. 90 percent silver dimes, quarters, or half dollars contain more than 723 troy ounces of the precious metal.

But, coins could and did lose noticeable weight when heavily circulated. Among dealers, the most common standard used for the silver content of a $1,000 bag of “junk silver” is 715 troy ounces. I have seen some dealers use 710, 712, 718, or 720 ounces for the stated content.

The average silver content of bags of Barber coinage, Mercury dimes, Standard Liberty quarters, and Walking Liberty half dollars are lower than that of bags of Roosevelt dimes, Washington quarters, and Franklin and 1964 Kennedy half dollars. Some buyers pay a modest premium to acquire only the 1964 Kennedy halves, which have minimal average circulation wear.

When the price of silver reached up toward $50 per troy ounce in January 1980, the refiners needed to protect themselves from paying for $1,000 face value of silver coins that contained a higher than normal percentage of well-worn “slicks.” At the market peak, they accepted bulk 90 percent coins on the basis of weight, not count. If the bag of coins was underweight it was either rejected or only taken at a discount.

When the spot price of silver again rose close to $50 in April 2011, refiners and wholesalers again protected themselves by checking weights as well as counts of 90 percent bags.

For the protection of my company’s customers, ever since we have weighed every $500 face value bag of U.S. 90 percent silver coins to ensure that it weighed at least 27-1/4 avoirdupois pounds (which includes 3 ounces for the weight of the canvas bag and the bag seal). That means that every $1,000 of 90 percent coins we deliver weighs a minimum of 54 pounds and 2 ounces (and almost all weigh several ounces more). That was sufficient to have met the standard weight required by wholesalers and refiners when they imposed both minimum weight and count requirements that year. We expect this strictness to make sure that our customers do not get an excessive number of well-worn coins in what they purchase from us will pay off in the future when silver prices may be many multiples of current levels.

If you purchase bags of junk silver, be sure to ask your dealer if they make sure that the coins you receive will meet any minimum weight requirements that may again be imposed sometime in the future. If not, you may want to either avoid that dealer or to only deal with them if there is a significant price discount. Someday, the weight as well as the count could matter in how much you are paid when you sell such coins.

Patrick A. Heller was the American Numismatic Association 2012 Harry Forman Numismatic Dealer of the Year Award winner. He is the owner emeritus and communications officer of Liberty Coin Service in Lansing, Mich., and writes “Liberty’s Outlook,” a monthly newsletter on rare coins and precious metals subjects. Past newsletter issues can be viewed at Other commentaries are available at Coin Week ( His radio commentaries titled “Things You ‘Know’ That Just Aren’t So, And Important News You Need To Know” can be heard at 8:45 a.m. Wednesday and Friday mornings on 1320-AM WILS in Lansing (which streams live and becomes part of the audio and text archives posted at

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