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 Replies: 21 / Views: 4,199 |
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Pillar of the Community
Canada
2301 Posts |
I was going to do a paper on die stresses a while ago. This pair is cool as the collar was included. The correlation between die and collar failure needs research. Just a thought.  |
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Pillar of the Community
Canada
693 Posts |
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Pillar of the Community
Canada
2632 Posts |
Nice is what I think, and appears to perfect to be coincidental.
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Valued Member
Canada
496 Posts |
Interesting that the '99 die crack has progressed farther into the coin than the '00 crack.
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Pillar of the Community
 Canada
9864 Posts |
Quote:
This pair is cool as the collar was included. A die crack to the edge of the rim does not necessarily indicate damage to the collar. Can you show pics of the edge of the coin so that we can see the area of collar failure? "Dipping" is not considered cleaning...
-from PCGS website
Edited by DBM
04/02/2016 12:32 am
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Moderator
 Canada
10458 Posts |
Is that the same spot as where the 1996 Far 6 cracks propagate from? (I am referring to the coins I sent you, and the ones you showed Henry - who subsequently wrote about them)
"Discovery follows discovery, each both raising and answering questions, each ending a long search, and each providing the new instruments for a new search." -- J. Robert OppenheimerContent of this post is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License. See: http://creativecommons.org/licenses...0/deed.en_USMy eBay store
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Pillar of the Community
Canada
9864 Posts |
Die cracks through the A are quite common in this era. Why? For a triennial set here's a '99 on ebay 172150046085"Dipping" is not considered cleaning...
-from PCGS website
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New Member
Canada
35 Posts |
Nickelsguy.....you should get that ebay 1999.....would be nice to have 3 consecutive years with similar diecracks... |
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Pillar of the Community
Canada
2360 Posts |
Quote:
Interesting that the '99 die crack has
progressed farther into the coin than the '00 crack. I thought that the progressive nature of a die crack means that a later die state sees the size (length) of the crack progressing to a larger crack as time went by and coins were pressed. Where you see a shorter d/c in 2000 is odd to me. In the ebay example - 1999, the d/c extends to the island whereas the 2000 example it fades in the field just NW of the A in CANADA.  How does this happen? Edited by SilverDon
04/02/2016 02:29 am
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Pillar of the Community
Canada
9864 Posts |
Quote:
How does this happen? Die cracks are generally progressive, they grow with time and use. However these are not from the same die.That these are in the same place indicates a flaw in the material or process used to make the die common to those years,or something peculiar to the striking method or equipment creating abnormally high stress in that area, or a combination of die and striking problems. "Dipping" is not considered cleaning...
-from PCGS website
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Pillar of the Community
Canada
2360 Posts |
Thanks DBM.
Edited by SilverDon
04/02/2016 09:32 am
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Pillar of the Community
Canada
3234 Posts |
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However these are not from the same die. I agree....but I will be on the lookout for any of these..and then pass them on to Mikey.. |
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Pillar of the Community
 Canada
2301 Posts |
Same denticle Roger.
DBM I have no ability to image the edge sorry.
The 1999 now fits between these two. Thanks to DBM.
Thank you Derek!
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Pillar of the Community
Canada
1049 Posts |
MM, I pulled aside early stage 1996-2000 of this DC where the crack is from the tip of the A to the beads, this pic is the 2000. PM me if you can use pics of the others or perhaps all of the coins. Jon DBM more proof of what you mentioned in your post here.  Edited by M_d_in_guy
04/04/2016 05:06 am
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Pillar of the Community
Canada
2301 Posts |
PM sent MD.
My research shows me that as the die crack progresses it puts extra pressure (shear) on the collar as well cracking. With the reverse die and collar not being in the same location adjacent to each other the collar crack appears to spread slightly as is apparent on the flat of the rim in the two coins above. The same is evident on the 1996 5 cents with a very small reverse crack which also has damaged the collar.
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Pillar of the Community
Canada
1049 Posts |
Thanks Mike, PM replied to. I'll check the rest of my stash and see what else there may be along this line. That would be cool if you could get the complete stages of progression right to the very last when it was changed out, be it any or most of the years.
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Replies: 21 / Views: 4,199 |
Posted 04/01/2016 10:52 am
