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<p>[QUOTE=&quot;19Lyds, post: 1622403, member: 15929&quot;]I&#039;m gonna disagree with you Doug. Annealing &quot;may&quot; have occured with trays in the old days but certainly not during todays mass production of millions of coins. Strictly speaking post 1965 when the copper nickel planchets were introduced and more specifically with the CnClad Kennedy Half and Eisenhower Dollars.</p><p><br /></p><p>The &quot;chatter&quot; the OP is referring to is most certainly introduced during the annealing phase and as such, that chatter, which is most prominent near the edges of the struck coin, can be struck out with good metal flow during the striking process. Metal flow is the direct result of striking pressures and for the CnClad coins, increased striking pressures caused premature die failure. Dialing down the striking pressures produced enough detail for the coin to meet spec but left that annealing chatter near the edges of the coin. Poor metal flow also leaves this chatter in the high points of the coins as well. Namely the cheek and chin areas. This is one of the reasons that these CnClad coins look so terrible.</p><p><br /></p><p>No doubt, during the pre-strike manufacturing process, planchets are tumbled enough to create these hits which are most evident on the Philadelphia IKE&#039;s and Kennedy&#039;s. The Denver Facility had a die repair shop but lacked the ability to create dies in the 70&#039;s. As such, damaged dies were &quot;repaired&quot; until no longer serviceable. These repairs are quite evident on the Eisenhower Dollars from Denver.</p><p><br /></p><p>Notice the flattened Date on the OP&#039;s coin. This is quite common on these CnClad coins and is a direct result of lower striking pressures.</p><p><br /></p><p>The manufacturing of die&#039;s AND coin&#039;s changed dramatically when silver was replaced with the much harder CnClad media. The end result reflects that difference in the form of planchet chatter commonly referred to as annealing chatter. It exists oin virtually every coin the US Mint produces with the exception of special collector coins (i.e. Satin Finish and Proofs)</p><p><br /></p><p>Below is a lightweight Silver Clad Eisenhower which shows evidence of this chatter.</p><p><br /></p><p>[ATTACH]230620.vB[/ATTACH][ATTACH]230621.vB[/ATTACH]</p><p><br /></p><p>Since the above coin is 1.5 grams lighter than spec, it can be assumed that the planchet was thinner than the norm. A thinner planchet creates a weaker strike with the net result being the chatter is not removed due to incomplete metal flow.</p><p><br /></p><p>To address the high point chatter problems, the US Mint toned down the relief of the Kennedy Hald Dollar over a series of years creating the now, nearly flat coins that we see today. In 1972, the US Mint started experimenting with harder die steel so that pressures could be adjusted to accomodate the harder planchets. The net result shows up with the 1974 and later IKE&#039;s in that MS67 is fairly rare until that time.</p><p><br /></p><p>Ti make a boring story short, I&#039;d summarize by saying that the manufacturing processes changes significantly when CnClad was introduced to step up coin production.[/QUOTE]</p><p><br /></p>

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