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CONECA (pronounced: CŌ´NECA) is a national numismatic organization devoted to the education of error and variety coin collectors. CONECA focuses on many error and variety specialties, including doubled dies, Repunched mintmarks, multiple errors, clips, double strikes, off-metals and off-centers—just to name a few. In addition to its website, CONECA publishes an educational journal, The Errorscope, which is printed and mailed to members bimonthly. CONECA offers a lending library, examination, listing and attribution services; it holds annual meetings at major conventions (referred to as Errorama) around the country.

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Pre-Strike-Damaged-Penchant Error

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  • Pre-Strike-Damaged-Penchant Error

    Error-Ref.com, lists "Rockwell Test Mark in Planchet, in Part V, Planchet Errors, Pre-Strike Damage. This error happens when a penchant used for Rockwell Hardness Test, which is damaged because of the indentation caused by testing, instead of being discarded as prescribed in the test procedures, is mixed into a penchant batch and, subsequently, put through the minting process. Then, the coin thus produced will show a Rockwell test mark on it, exhibiting a kind of dimpled area which may be different in shape and size from the spherical indentation caused by Rockwell test, due to the plastic deformation and metal flow that occur during the die strike. The resulting damage is expected to be impossible to induce artificially on an existing minted coin, for the plastic deformation and metal flow is a natural process which can't be easily produced manually.

    I showed photos of such marks in this Forum some time ago, but I find that almost all, who commented, saw the damaged area and concluded right away that it is Post-Mint-Damage (PMD), without examining the damage and its features in detail. To convey the findings better, the original photo showed as well as a new one taken with a scale in 1/16-ich interval are given below. 1/16-inch is the diameter of the ball indenter used for Rockwell test.

    Could anyone induce the damage, including the altered T and R, in a struck coin? What tool would he use to simulate the detailed features of the damage? Therefore the only logical conclusion is those features are created naturally at the time of striking. The die, which impressed R on the concave surface of the Rockwell indentation, lightly because it was below the plain surface of the penchant, together with plastic deformation and associated metal flow, are the most likely cause of the feature of R, which is somewhat faint and larger and thicker than the normal shown in the 2nd photo. Therefore, I firmly believe it is a Pre-Strike-Damaged Penchant Error.

    For comparison, a photo of undamaged cent is also shown.
    Attached Files

  • #2
    We have given you our expert opinion. You can use it as you would like.....Minterrors and me are experts in our fields. I am an attributer for CONECA, with the minting process specialty. This could not have been struck in this faction. The mark on the rim above the T can not happen with a collar..... Sorry.... this is Post Mint Damage not pre strike damage.
    Last edited by onecent1909; 01-16-2024, 08:47 PM.
    CONECA Attributer: John Miller

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    • #3
      Some additional, logical thought for this coin. For Rockwell hardness tests, they are typically done once and that measurement is recorded and the planchet is then put into a container to be destroyed.

      In my opinion, It makes no stinking logical sense to mutilate a planchet with many tests on the same planchet. It does nothing for a test. The US Mint would take planchets at different levels of temperature or hardness, to find that near perfect match. One test per planchet is all that is needed.

      Should the original poster send this in to a third party grading service like I stated before, an expert in the field will offer their opinion. Again, for closure and knowing the truth of what this is, it's up to the owner to accept the risk and truth to send it in to be examined. Again, in my opinion stand by for it to be returned, upgradeable and in a plastic body bag. Be elated if it comes back as a winner.

      I could be wrong on this - I am human and learn from mistakes. But in this case, I think my chances are pretty good on my assessment. I have been collecting for over 50 years and I have been in the errors and variety field since the early 1980s.

      I personally believe the original poster will more than likely not change his mind on the subject coin and therefore, further posts from me on this post or others from this poster are likely to be politely debatable, to to point of flogging a no longer alive animal. With that being said, this is my last post to the original poster.
      Gary Kozera
      Website: https://MintErrors.org

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      • #4
        onecent1909, @MintErrors
        Thank you for your kind comments. However have you given any thought about "How those features of damage seen in the photos could be produced manually?" I do not believe you, technical experts in Numismatics, would believe that those damages were produced accidentally or by shooting a coin with a BB gun, which, many think, is the cause. The most critical issue, that is evaded here, is that how these damages we see can be produced by other means except the minting strike.

        I have thought about why there are so many damage marks. The only logical answer I could come up with is as follows. Someone practiced Rockwell tests on a piece of coil material, not on individual penchants. That piece should have been discarded. But mistakenly it was put into blanking machine, producing blanks with many test indentations, which subsequently put through the rest of the mint process. The mark on the rim, believed to be impossible by onecent1909, could be caused by a small part of a test indentation whose center was located outside of the blank (we could imagine there were many more indentations in that test piece).

        I would not wish to bother you. However as technical professionals in numismatics, it would be imperative for us to consider all possibilities based on sound scientific reasons to explain what we observe in this particular coin. Without explaining how these damages could be produced and concluding them as PMD would be injustice to science.

        Comment


        • #5
          To provide damage size estimation, photos taken with a scale in 1/16-inch interval are shown. How could all these damages be induced accidently or artificially, other than the minting strike itself?
          Attached Files

          Comment


          • #6
            Originally posted by Francis View Post
            The most critical issue, that is evaded here, is that how these damages we see can be produced by other means except the minting strike.
            I have thought about why there are so many damage marks. The only logical answer I could come up with is as follows. Someone practiced Rockwell tests on a piece of coil material, not on individual penchants. That piece should have been discarded. But mistakenly it was put into blanking machine, producing blanks with many test indentations, which subsequently put through the rest of the mint process. The mark on the rim, believed to be impossible by onecent1909, could be caused by a small part of a test indentation whose center was located outside of the blank (we could imagine there were many more indentations in that test piece).

            I would not wish to bother you. However as technical professionals in numismatics, it would be imperative for us to consider all possibilities based on sound scientific reasons to explain what we observe in this particular coin. Without explaining how these damages could be produced and concluding them as PMD would be injustice to science.
            ..... first we need to think the opposite of what you stated.....we need to think how are coins made?
            start with sheets (or coils to sheets) of metal punched to blanks.... blanks processed to planchets.... planchets struck by 2 dies and a collar, liquifying the metal to flow into designs and rims.

            1) now... IF the mark on the rim was located outside of the blank (which is punched out of the rockwell tested sheet) it would HAVE to be on the edge of the sheet... or it could not be on the outside the blank, as blanks are punched out of the metal ..... IF that was the case... the coin would have a straight clip or a ragged clip from the edge of the metal sheet..... it does not so this cant be.....

            2) the striking with a collar would make sure that the coin is in the normal diameter.. and there can be NO metal outside the round (as that mark is)... it has metal outside of the round, and the rest of the coin is the right diameter so it cant be.....

            3) When it comes to TRUST and the "testmark" at the R.... The R in the die is a lower part of the dies. the field is the highest part of a die...IF there was a rockwell test mark that would be where the R would end up being on a planchet...... then there would be NO R visible as there would be no metal to flow into the recessed R in the die..... you can see traces of the R in the pic so it can not be.

            This is the simplified science of how a coin is made... (I personally have studied how coins are made and teach a class on it at the ANA summer seminar)....and how these can not be pre strike damage.... therefore.... these are post strike damage of some type.... what type and how... not of a concern for if this is an error....

            IF you believe we are wrong... Please submit to PCGS, NGC, ANACS. you will not get a favorable ending stating that this is a rockwell test mark, or many test marks....

            I too will not engage in this thread anymore as the scientific process has proven these could not be done in the minting process. Thank You for your questions.

            CONECA Attributer: John Miller

            Comment


            • #7
              From reading materials on Rockwell test marks available on internet, it appears that, so far, there is only one that was authenticated as a real Rockwell test mark. That one was from a 1971-S Lincoln cent, shown in the attached photo (from Error-Ref.com), which was authenticated by late Mr. Devine. It is certain that Mr. Devine thought about various possible causes of that damage, but, in the end, concluded that it must be an authentic, real test mark based on its odd shape and the smoothness of its inner surface. Now I understand that there are doubts about Mr. Devine's authentication and, it seems that opinions are leaning toward against his conclusion. From all of these, it is evident that the Numismatic Society does not know currently what to expect when a damaged planchet with a Rockwell test indentation is put through the minting process.

              Here we are dealing with many damages which are much more complex than the one found in 1971-S Lincoln cent (except one near LIBERTY which is similar). I believe the mark in 1971-S cent is a real Rockwell test mark. And I admire late Mr. Devine for his keen scientific insight and understanding and his courage to conclude that the mark he examined could not be produced by accident nor manually, despite numerous objections by other colleagues.
              Attached Files

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