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<p>[QUOTE="Pete Apple, post: 3574169, member: 103982"]I think Fred is correct, however there are circumstances in which a mark can be identified as "likely".</p><p><br /></p><p>Elsewhere, I have noted the following with regard to a test mark on a planchet:</p><p><br /></p><p>"We are accustomed to thinking that if an imperfection on a coin satisfies the diagnostics associated with a particular mint error, then we can assign it to that mint error. For example, a cud (marginal die break) is unlikely to be confused with any other defect. In other words if it looks like a duck, walks like a duck, and quacks like a duck, then it is a duck!</p><p><br /></p><p>However, with a Rockwell Test Mark, this way of thinking may not be appropriate. It may be possible for an indentation to match the description of a Rockwell Test Mark without actually being a Rockwell Test Mark. The only way I know to be certain that a mark came from a Rockwell Test is to have actually witnessed the test which, of course, is not possible! The most we can say is that a particular indentation meets the expectations of a Rockwell Test Mark. A Rockwell Test Mark should have a smooth, hemispherical cross section profile and assume the shape of a circle or an oval (if it is adjacent to a device). There should be no anvil effect (a raised area on the opposite side of the coin) and no pressure ridge around the circumference of the depression.</p><p><br /></p><p>I know the odds are low that a Rockwell Test Mark will make it through the minting process. I am also thinking that the odds are low – or even much lower – that a random contact mark on a coin</p><p><br /></p><p>• would have the same hemispherical cross-sectional profile as a Rockwell Test Mark AND</p><p>• show the same depth as a Rockwell 15T test mark AND</p><p>• have the same diameter as a Rockwell 15T test mark (adjusted for the strike) AND</p><p>• not leave a pressure ridge AND</p><p>• not leave an anvil effect (bulge) on the opposite side of the coin.</p><p><br /></p><p>I know of no way to calculate the probability of all those things occurring as a result of random post-mint damage – but I think it would be astronomical. It would be even more improbable for all these things to occur twice on the same coin as the result of random post-mint contact..."</p><p><br /></p><p>Since a mark can only be identified as "likely" I think that a TPG will never certify a mark as being a Rockwell test Mark. I, too, will be interested in hearing the response of PCGS![/QUOTE]</p><p><br /></p>
[QUOTE="Pete Apple, post: 3574169, member: 103982"]I think Fred is correct, however there are circumstances in which a mark can be identified as "likely". Elsewhere, I have noted the following with regard to a test mark on a planchet: "We are accustomed to thinking that if an imperfection on a coin satisfies the diagnostics associated with a particular mint error, then we can assign it to that mint error. For example, a cud (marginal die break) is unlikely to be confused with any other defect. In other words if it looks like a duck, walks like a duck, and quacks like a duck, then it is a duck! However, with a Rockwell Test Mark, this way of thinking may not be appropriate. It may be possible for an indentation to match the description of a Rockwell Test Mark without actually being a Rockwell Test Mark. The only way I know to be certain that a mark came from a Rockwell Test is to have actually witnessed the test which, of course, is not possible! The most we can say is that a particular indentation meets the expectations of a Rockwell Test Mark. A Rockwell Test Mark should have a smooth, hemispherical cross section profile and assume the shape of a circle or an oval (if it is adjacent to a device). There should be no anvil effect (a raised area on the opposite side of the coin) and no pressure ridge around the circumference of the depression. I know the odds are low that a Rockwell Test Mark will make it through the minting process. I am also thinking that the odds are low – or even much lower – that a random contact mark on a coin • would have the same hemispherical cross-sectional profile as a Rockwell Test Mark AND • show the same depth as a Rockwell 15T test mark AND • have the same diameter as a Rockwell 15T test mark (adjusted for the strike) AND • not leave a pressure ridge AND • not leave an anvil effect (bulge) on the opposite side of the coin. I know of no way to calculate the probability of all those things occurring as a result of random post-mint damage – but I think it would be astronomical. It would be even more improbable for all these things to occur twice on the same coin as the result of random post-mint contact..." Since a mark can only be identified as "likely" I think that a TPG will never certify a mark as being a Rockwell test Mark. I, too, will be interested in hearing the response of PCGS![/QUOTE]
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