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<p>[QUOTE=&quot;GDJMSP, post: 2293305, member: 112&quot;]When looking at coins like these you need to think about what actually happens to the metal, in the different areas, when a coin is struck. And think of it as occurring in slow motion. The high points on the die are the fields and they are flat. So when the die pushes against the metal of the planchet, the field areas are touched first, and they are pushed straight down, or up as the case may be for each die, and in a flat plane. This causes the metal underneath, the metal that is not actually touching the die to be pushed outwards, away from the pressure point. While the metal that is actually the touching the die is pulled and stretched. This is what we refer to as metal flow, and it is of the metal flow that creates the luster we see on a coin.</p><p><br /></p><p>However, what happens to the metal in the devices areas, legends, date, etc. is quite different. And please try to visualize this. This metal does not move in a flat plane like the areas in the fields. Instead this metal is being pushed, outwards and upwards at the same time, by the metal that is around it and underneath it. This is caused by the pressure on the metal from the fields areas. And when this metal that is in the devices areas is pushed by the pressure from underneath, the surface of the flat metal of the planchet kind of bubbles upwards. It is pushed and stretched in all directions at the same time as it moves into the recesses of the die. And since the recesses of the die are all at various different depths, the metal in the shallowest depths touches the die first. But it it doesn&#039;t stop there, it continues to move because it is still under pressure from the metal underneath it. And it moves to fill the deeper recesses of the die. It is only when the metal fills all of the recesses, or when the pressure stops, that the metal stops moving, or flowing.</p><p><br /></p><p>Now, imagine if you will, prior to this entire process the planchet has striations on it. The striations in the fields are affected because they are being pulled and stretched, but because they are moving in a flat plane the effect is somewhat minimal, leaving them still visible on the struck coin, but yet different looking than they were before the strike. They will be a little wider, though more shallow in depth than they were originally but their consistency in appearance will basically be the same on a relative basis.</p><p><br /></p><p>With the metal that is in the devices areas however, this is not the case. Because that metal is being pushed upwards, or downwards, as the case may be depending on whether it&#039;s the hammer die or the anvil die,&nbsp; from underneath that metal is subjected to much more stretching and the bubbling up effect than the metal in the fields areas is subjected to. This causes the striations that were on the planchet to change shape, becoming even wider and even more shallow as the metal continues to move. This results in the striations in the devices areas being a completely different shape and depth than the striations in the fields area were.</p><p><br /></p><p>So when you look at a coin struck on a planchet that had striations, it is when the striations in the two areas look different that you know the coin was struck on a planchet with striations.</p><p><br /></p><p>If the striations you see on the coin look basically the same however, or the striations in the devices areas are deeper than those in the fields, then you know those striations occurred <u>after</u> the coin was struck, not during the strike.</p><p><br /></p><p>I will readily agree that there are many coins in TPG slabs, with striations like those on this coin, where it is assumed that they are roller marks, or planchet striations in other words. But that is because few ever think the striking process all the way through in regard to what happens to the metal during the strike. Once you do, it becomes obvious.</p><p><br /></p><p>Because the recesses in the dies are at different depths, and because those recesses are filled by flowing, moving metal, any previously made striations on a planchet cannot retain the same and equal appearance. It just can&#039;t happen because of the way the metal is forced to move.</p><p><br /></p><p>Now, also consider what would happen to a struck coin if it was subjected to an outside force and pushed or slid against a fixed object. Kind of like a coin being pushed along on the floor if you will, just as an example. If the floor is rough, or has even a minutely uneven surface, like maybe the concrete floor of the mint, the high points of that coin (the devices) will have deeper scratches on it than the low points (the fields) will. This will result in the coin looking just like the coin in this thread. </p><p><br /></p><p>Of course the same thing could happen if the flat edge of a scoop shovel were slid across the face of a coin as well. And yes, these coins were put into bags with scoop shovels.</p><p><br /></p><p>So consider, given all of the above, which scenario seems to be the most likely to have happened ? Plancet striations, or post strike damage. You are welcome to choose whichever you prefer, but I know the one I pick.[/QUOTE]</p><p><br /></p>

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