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Message:: [QUOTE="keemao, post: 2230681, member: 43972"]Forgot to add NGC's response to my email. "Though the advantages of using close collars over open collars were many, including uniformity of diameter and raised rims that protected a coin from wear, they did present a new set of problems for the mints to overcome. These collars had to be aligned properly with the obverse and reverse dies to avoid what U.S. Mint personnel called "finning." This phenomenon is better known to the coin hobby as a "wire rim," and it resulted from metal being forced through a gap between the perimeter of the die and the inside diameter of the collar. If all these pieces fit together perfectly, a complete seal was achieved, and no wire rim would be seen—at least not on coins struck for circulation. With proof pieces, however, the multiple strikes required to bring out the coin's design fully often produced a fine wire rim on one or both sides of the coin. On the proofs struck since 1968, especially those reeded-edge pieces made from the very hard copper-nickel-clad composition, these wire rims are sometimes sharp enough to cut a person's skin if the coin is not handled carefully."[/QUOTE]