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 Replies: 23 / Views: 3,384 |
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Valued Member
United States
117 Posts |
The coin is a 2001 P 25C. The obverse at 7 o'clock has a oval shaped pit. The floor of the cup shaped depression is completely smooth. Corresponding to the obverse is a distortion of the R of North on the reverse. Rockwell hardness test: A Rockwell hardness tester is used to measure the hardness of metals at the US mint. It measures the depth of penetration of a steel or diamond tipped pin relative to the applied force. When applied to a planchet, the mark will appear as a small circular pit with a smooth floor. After the test, the planchet is discarded. If the tested planchet is struck by a die, the circular pit is distorted to oval as the coin expands upon impact. The picture of the 1971 S 1C is from ERROR-REF.com It was authenticated by John Devine. Unambiguous - There are no coin samples that we can point to that have only one interpretation for this type of damage that being the Rockwell test. Also, the test is normally done in the center of the field. Your thoughts and whether I should have this coin authenticated if that is even possible.     |
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Pillar of the Community
United States
3237 Posts |
Was the penny photo uploaded by mistake? It's helpful if you only upload one coin per thread. The quarter looks like it might be a strike through as I'm not seeing any evidence that material was forced out of the cavity.
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Pillar of the Community
United States
7078 Posts |
IMO your "dent" is much larger than the Rockwell test punch and with the damage to the opposite side I would conclude that you have a quarter with PMD |
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Pillar of the Community
United States
7516 Posts |
The quarter has taken a hit and is considered damage, note the effected area on the opposite side as well.
Edited by Chase007
05/05/2020 6:01 pm
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Moderator
 United States
56855 Posts |
Type Rockwell test in the search box. John1  |
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Bedrock of the Community
Australia
21788 Posts |
I stand to be corrected, (haven't checked), but I understood that the Rockwell Test was done with a cone point.
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Pillar of the Community
United States
7516 Posts |
Quote:
I understood that the Rockwell Test was done with a cone point.  |
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Moderator
United States
34430 Posts |
As I recall the Rockwell B hardness test uses a ball indenter (as does the Brinell hardened test).
"If you climb a good tree, you get a push."
-----Ghanaian proverb
"The danger we all now face is distinguishing between what is authentic and what is performed."
-----King Adz
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Valued Member
 United States
117 Posts |
I wasn't drawing any conclusions in my post per se. However in reading some of the comments I think I am able to be reasonably certain of the cause of the coin error. Thank you.
1.. Samcoin - I am sorry that my post wasn't clear enough to understand that it was about the one coin a 2001 P 25C. The picture of the other coin was an illustration of a coin with a rockwell test mark. It is critical to the post.
2. Greasyfingers - dent is that your conclusion? After looking at it again, I am thinking that they are both the same size
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Bedrock of the Community
United States
10635 Posts |
PLEASE, one coin per thread. Your coins suffer from PMD, nothing more. |
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Bedrock of the Community
United States
62064 Posts |
There is a wave splashing out on the rim and the opposite side is showing metal disturbance from a contact mark on the opposite side. PSD |
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Valued Member
United States
117 Posts |
Thank Coop - You always have an excellent observation. I will look for that.
Merclover - PLEASE read posts before commenting!
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Bedrock of the Community
United States
10635 Posts |
Windex, YOU need to read posting guidelines.
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Moderator
United States
56855 Posts |
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Valued Member
United States
117 Posts |
John1 thank you. I did read it last night. It was a very good read. My curiosity remains on how a coin could get damaged like that accidentally or on purpose. Such matters will never be solved - still curious.
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Pillar of the Community
United States
2739 Posts |
I no longer consider the imaged cent as having a Rockwell planchet test mark. As far as I'm concerned ALL purported Rockwell planchet test marks are now suspect. As far as the quarter goes, the perturbed letters on the reverse are consistent with post-strike damage. It's also too large, its location is all wrong, and the presence of scour marks all disqualify this depression as a Rockwell test marks.
Error coin writer and researcher.
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Replies: 23 / Views: 3,384 |
Posted 05/05/2020 2:27 pm
