Collectors have found the standard mistakes made by the U.S. Mints on other coin issues to be present in the State quarters as well. Most claims regarding missing letters or design features are usually a case of a weak strike, a filled die, or the detail
of the design being polished out of the dies. These abnormalities are generally considered mint varieties and do not necessarily add numismatic value to the coin.
There have been several reports of rotated-reverse errors on the new U.S.commemorative State Quarters, particularly on the early issues. To test for this error, hold the quarter "heads up" with your fingers at 12 and 6 o'clock, turn the quarter over to either side. The normal orientation of the reverse of the coin will face you as up side-down. A rotated-reverse error coin will appear as right side-up. On October 18, 1999, Coin World reported that rotated die errors of 10 to 90 percent have been reported for Delaware, Pennsylvania and New Jersey quarters. Reports of 180-degree rotated-reverse errors have been found on the first five quarters produced for the program. In general, dealers and collectors are waiting for the market to define itself before assigning definitive values. Visit a local ANA member dealer for an up-to-date evaluation.
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