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 Replies: 9 / Views: 2,025 |
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Pillar of the Community
Canada
9165 Posts |
How can you tell if you have a clipped cent or a PMD cent? |
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Valued Member
Canada
166 Posts |
A clip should line up perfectly with another cent like penny rim to clipped area. You will know when you look at it if it is clipped at the mint. Here is a double clip https://goccf.com/t/79413Edited by thatcanuckyguy
03/28/2011 1:38 pm
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Pillar of the Community
Canada
693 Posts |
I somewhat disagree with thatcanuckyguy. It's true another cent will often fit into the clipped area, but that's not always the case. Especially with larger clips, some deformation of the clipped area can happen. There should be a close match though.
A better dianostic for an authentic clipped cent is to look for Blakesley Effects.
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Bedrock of the Community
United States
12437 Posts |
Well, straight and elliptical clips will definitely not fit with another coin but that is not a great diagnostic regardless because all you have to do it is take the proper bite out of a coin for it to match.
Genuine incomplete(clipped) planchet errors have a couple diagnostics. The primary one is the Blakesley Effect, it is an area of weakness 180 degrees from the clip. The Blakesley Effect is caused when an incomplete planchet is sent through the upsetting mill to form the protorim before striking. The upsetting mill works by force spinning a blank through a narrowing channel which causes the diameter to shrink slightly while the rim is built up. If a blank has smaller than normal diameter, the pressure from the upsetting mill will not be great enough to upturn the rim opposite the clip.
With very small clips(<5%), the Blakesley Effect may not be present. In that case, look at the area of the rim in question. Is the rim tapered at the site of the clip or does it end abruptly? Do devices seem to "flow" toward and over the clip? Abrupt sharp endings equal someone cutting the coin. On a genuine error, the planchet will flow to fill the void when it is struck. This metal flow will taper the rim and cause the devices to weaken at the edge.
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Valued Member
Canada
166 Posts |
Thank you biokemist6 for clearing up and educating those of us who are still learning!
Much appreciated.
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Pillar of the Community
 Canada
9165 Posts |
Thanks bio, that does help.
canuck you beat me typing
Edited by mcshilling
03/28/2011 3:54 pm
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Pillar of the Community
Canada
1166 Posts |
 I'm adding this to be used in conjunction with biokemist6's explanation. This illustrates (basically) clipped planchets. The ones that are struck on the left hand side will have ragged edges; the ones at the top and right hand side are the straight clips and the ones in the middle area are the typical curved planchets. The two images below shows the Blakesley effect which is directly across the coin from the clip. Notice the weakness on the rim. Also, note how the devices are pulled down into the clip.   |
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Valued Member
Canada
166 Posts |
That is awesome ikandiggit!  Thank you much! |
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Pillar of the Community
Canada
9165 Posts |
The coin ikanddiggit posted is just like the one I have.
Great info.
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Valued Member
Canada
248 Posts |
Thanks -biokemist6- It's real nice to read a great educational post! ---Thanks again for taking the time.  And --- Thanks -ikandiggit- I guess we can learn from you too!  nice add on with pictures brings it together! Good job!
Edited by commoncents13
03/29/2011 04:00 am
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Replies: 9 / Views: 2,025 |
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Posted 03/28/2011 1:56 pm
