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5 potentially undocumented mint errors

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  • 5 potentially undocumented mint errors

    Good morning. Through the cataloging of a huge estate collection, I have come across a vein of coins as such...My favorite coin the 1056 D/D but couldn;t find it in th books. One book called something similiar to an RPM marked NEW RPM and now F #satin finish 2009-D all reverses
    Another of the experimental Proof surfaces used on U.S. gold coins after 1907. The dies were treated in some manner to create the silky surfaces imparted to the coins 2003-2010. Also some oddities from the 80' Denver, (2) 1982-D Large 3.11, (1)and (1) 1980 D LD 3.1 and 1986 -D 2.4 struck on Brass or another experimental planchet. The first 3 weigh exact but have No copper at all apparently 100% zinc, the condition is AU BU from Sealed Brinks bank rolls and US MINT BU GEM rolls .Could they exist? They don't in many references. One dealer said 3c each! I asked if he would trade me a couple of MS 1885 CC Morgans then. lol should I have taken his 1st offer??? Thank You Mike Diamond
    Attached Files

  • #2
    In the future, please post one inquiry and one set of images related to that inquiry at a time. Otherwise it becomes overwhelming.

    Your 1956-D cent has RPM no.1

    The gray-colored cents dated to 1982 and later may or may not be struck on genuine unplated planchets. Such errors are easily faked and require detailed examination under a microscope. The gray-colored 1980-D cent was clearly plated outside the Mint.

    Brass-colored cents do not necessarily indicate something odd about the alloy. Cents turn all sorts of colors. Again a detailed study of all its specifications and surface properties would be essential to any diagnosis.
    Last edited by diamond; 05-05-2019, 06:13 PM.
    Mike Diamond. Error coin writer and researcher.


    • #3
      Mr. Diamond, since there was an 83 D as well as brass plated strikes from these years, 1985 D 1997 D 1997 1998 (Cited from: https://www.cointalk.com/threads/lin...-strikes.4769/) is it conceivable that Denver coiners might have missed a brass planchet from 85 had it gotten stuck internally then dislodged from a machine vibration? Or is this statement I took off the net a more viable scenario....The brass plated cents were created when zinc planchets got stuck in the plating barrel they would dissolve and contaminat the plating solution. Then when later batches of blanks were plated instead of being plated with pure copper, they got a mixture of copper and zinc. In other words Brass. And they aren't a true mint error because the mint doesn't make the planchets, and the "brass" plating composition varies all over the place. And since the solution starts becoming contaminated with the very first batch of blanks plated you could say that ALL of the plated cents are brass plated with the composition of the brass on every batch being different. Would I need to submit these to TPS or will an attribution firm look at them? I have found 2 more cladless 84.-D and another brass colored 2.4g 82-D. (have you written any articles on this for CW? I saw one a lady wrote 10 years back) Thanks for the help, NM


      • #4
        Cents with brass-colored plating do exist, ostensibly for the reason you mention -- too many zinc ions in the copper plating bath. They don't carry much value, so sending them in to be professionally graded would be a losing proposition.
        Mike Diamond. Error coin writer and researcher.


        • #5
          Thank you for this information. As to the unplated examples, you mentioned some detailed analysis would be needed. If found correct would they bring enough of a premium these days to qualify having them studied? 607588-1.jpg
          Attached Files
          Last edited by tamster; 05-06-2019, 03:23 AM.


          • #6
            Genuine examples of cents struck on unplated planchets seem to bring between $75 and $100 on eBay these days.
            Mike Diamond. Error coin writer and researcher.