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<p>[QUOTE=&quot;GDJMSP, post: 966668, member: 112&quot;]Yes, I think they were very wrong.</p><p><br /></p><p><br /></p><p><br /></p><p><br /></p><p><br /></p><p>I agree that you are willing to accept those as planchet marks. But I do not for 1 second agree that they are planchet marks. Those are contact marks.</p><p><br /></p><p>&nbsp;</p><p><br /></p><p>But that is not how it works. I have explained in many threads how metal flows, but it seems it is either always forgotten or ignored. Guess I&#039;ll try one more time.</p><p><br /></p><p>When a coin is struck is is being squeezed between two opposing forces - the dies. Now the high points of the die are the fields and these high points come into contact with the planchet - the planchet is flat except for the outer edge that has been run through the upset mill. The first portion of the planchet that comes into contact with the dies are where the fields of the dies are. These areas are then pushed inwards towards the center of the planchet (if you were looking at it edge on) from two opposing directions at the same time. </p><p><br /></p><p>Now the metal of the planchet that the fields of the die is touching does not move at all, there is no metal flow there on the surface. The metal flow occurs in the center of the planchet. I don&#039;t mean the center of the circle either, I mean the center of the planchet in it&#039;s thickness. In other words the metal that is in between the top layer of the planchet and the bottom layer of the planchet is the metal that is moving. And it is moving because it is being squeezed at a great pressure. And as that metal moves it bubbles up and fills the areas in the dies that are holes. So any marks that may have been on the planchet that correspond to a hole in the die are obliterated by this bubbling up the metal as it flows to fill those holes. That&#039;s why there cannot be planchet marks on the high point of a coin. It&#039;s physically impossible.</p><p><br /></p><p>Now only at the very last stages of the strike can the metal of the planchet that is actually touching the fields of the die move or flow. And even then it more stretches than flows for there is little to nothing left to fill in the dies. And the most movement that occurs in this metal will be at the edges of the holes in the die, not at the center of the fields. That metal moves or flows the least of all.</p><p><br /></p><p>Where people make their mistake is that they think of the metal on the top and the bottom of the planchet as being the metal that flows. But this is wrong. It is the metal on the inside, the metal that cannot be seen or touched by anything that is moving. It happens the same way when you squeeze anything - the material in the center is what moves, not the material that actually has the pressure upon it.[/QUOTE]</p><p><br /></p>

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