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<p>[QUOTE=&quot;mithril21, post: 3461845, member: 102153&quot;]Hope you don&#039;t mind entertaining a slightly different theory.</p><p><br /></p><p><a href="https://www.coinworld.com/news/us-coins/2015/09/cracked-planchets-may-resemble-other-forms-of-brittle-failure.all.html" target="_blank" class="externalLink ProxyLink" data-proxy-href="https://www.coinworld.com/news/us-coins/2015/09/cracked-planchets-may-resemble-other-forms-of-brittle-failure.all.html" rel="nofollow">https://www.coinworld.com/news/us-coins/2015/09/cracked-planchets-may-resemble-other-forms-of-brittle-failure.all.html</a></p><p><br /></p><p>The more I look at this, the more I think it was a cracked planchet error. The crack occurred prior to or during striking, but it did not fully propagate across the coin so the two pieces were still held together by some ligament. The crack is brittle due to possibly missing the annealing treatment, alloy impurities/defects, and the high constraint between the collar and dies (there was no room for it to deform). </p><p><br /></p><p>The damage on the reverse was a separate event that happened at a later time and may have been what finally broke the ligament apart. This strike shows more ductility because the coin was no longer constrained between the collar/dies so it had room to bend and deform. Someone may have tried to crimp or cold weld the pieces back together (there is some smearing of the fracture surfaces).</p><p><br /></p><p>I do not believe it cracked after striking because there had to be some applied stress to cause it to crack. The strike on the reverse would not cause a crack so far away from where it was hit (the stresses decrease further away from the strike) which is why I believe these were two separate events. If the coin was used in some way where it experienced tensile, bending, or compressive stresses, then I would expect to see more marks or damage on the surfaces apart from just the crack. The fracture surface also shows heavy oxidation which indicates it is an older fracture that has been exposed to the environment for a while.</p><p><br /></p><p>Getting into the specific fracture mechanisms, crack propagation path, loading conditions, etc. is going a little too deep into things and isn&#039;t really necessary to determine it is most likely a defective planchet.[/QUOTE]</p><p><br /></p>

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