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<p>[QUOTE=&quot;ToughCOINS, post: 7488812, member: 20480&quot;]While we should all agree that the flow lines are created by furrowing of the surface of the dies by displaced planchet metal taking the path of least resistance, the direction in which planchet metal flows to create the observed effect is not universally agreed upon . . .</p><p><br /></p><p>It is true that some metal flows toward the recesses in the die, and some toward the rim, but my observation has been that in the majority of the noticeable cases the flow is predominantly toward the rim, and not away from it.</p><p><br /></p><p>The recesses in the dies, and the annulus between the planchet and the collar define the volumes receiving displaced metal.&nbsp; Both are significant, and the ratio of one to the other varies from one coin design to another.&nbsp; But that ratio by itself does not determine how much metal flows inward and how much outward, as variations in planchet dimensions (both thickness and diameter) and striking pressure also influence the outcome.</p><p><br /></p><p>Much like a river starts inland as a stream, and grows in size as it picks up more water downstream and carves a larger channel as it heads out to sea, so too do the metal flows that furrow the coining dies.&nbsp; This is easily seen when comparing the fineness of the flow lines near the central devices with their coarseness near the rim.</p><p><br /></p><p>This phenomenon is made even more pronounced by the fact that coins, being round, require that material flowing toward the center must crowd into an ever smaller flow area, while that flowing outward meets less resistance because the flow area increases with an increase in radius.&nbsp; Think of it this way . . . dividing the coin into pie slices, the metal within each slice of pie must remain within the bounds of its own slice as it moves under striking pressure . . . it much more easily moves toward the rim than toward the center.</p><p><br /></p><p>The striking of the Ultra High Relief Proof Saint Gaudens Double Eagle supports this notion.&nbsp; The resistance of flow toward the central devices was so great, and so frustrated efforts to execute the design to its fullest, that the coins had to be struck nine times, with full annealing of the coin between each strike.</p><p><br /></p><p>In the case of your coin, the obverse die obviously saw a lot more service than most others, or had not been properly hardened, or both.</p><p><br /></p><p>Again, I&#039;m not disputing that metal flows to the center, but I do believe most of it flows toward the rim.&nbsp; Hopefully, this answers your question.[/QUOTE]</p><p><br /></p>

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