Message:

<p>[QUOTE=&quot;Oldhoopster, post: 2968272, member: 84179&quot;]I&#039;m not a metallurgist, nor have any experience with this metal system, but it looks like there&#039;s some funky stuff happening for 75Cu/25Zn above approx 575C.&nbsp; Maybe reheating planchets prior to striking could result in some phase transformation/segregation if they got above this temp.&nbsp; I would guess that any inhomogeneities would be more likely to come from the original alloying, but that&#039;s just my unsupported speculation.&nbsp; Also, I don&#039;t think reheating planchets would cause gas bubbles unless they were present in the original mixed alloy. </p><p><br /></p><p>I think it&#039;s entirely possible that this could be a reasonable explanation for the appearance of the coins you pictured</p><p><br /></p><p>I know there are some people with metallurgy backgrounds floating around on CT, so maybe they will chime in.</p><p><br /></p><p><img src="https://www.copper.org/publications/newsletters/innovations/2006/03/images/cuzn_phase.jpg" class="bbCodeImage wysiwygImage" alt="" unselectable="on" /></p><p>( ref:<a href="https://www.copper.org/publications/newsletters/innovations/2006/03/neptunes_daughters.html" target="_blank" class="externalLink ProxyLink" data-proxy-href="https://www.copper.org/publications/newsletters/innovations/2006/03/neptunes_daughters.html" rel="nofollow">https://www.copper.org/publications/newsletters/innovations/2006/03/neptunes_daughters.html</a> Other than the phase diagram, nothing else appears to be pertinent)[/QUOTE]</p><p><br /></p>

Your name or email address:

Do you already have an account?

• No, create an account now.
• Yes, my password is:
• Forgot your password?

Stay logged in