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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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1991 D Possible DDR?

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  • 1991 D Possible DDR?

    I'm too much of a novice to even guess if this is something of significance. Please offer your thoughts. WIN_20210222_11_12_27_Pro.jpg WIN_20210222_11_14_40_Pro.jpg WIN_20210222_11_15_13_Pro.jpg WIN_20210222_11_15_02_Pro.jpg WIN_20210222_11_13_54_Pro.jpg WIN_20210222_11_14_32_Pro.jpg

  • #2
    Plenty of plating issues...all over that coin. Pretty cool looking but unfortunately no premium associated with this damage.
    Bob Piazza
    Lincoln Cent Attributer

    Comment


    • #3
      This is a classic example of "strike doubling" something went wrong and it damaged the coin. The possibilities are endless how this occurred but the end result as Bob P. has mentioned is that it's a form of damage.

      Have a look at the list I made up which helps with doubled dies:

      Doubled Die (aka Hub Doubling)
      • Doubled Die (aka Hub Doubling) Prior to 1996, the Master die was placed in a high tonnage press
      • A blank working die was warmed up to make the transfer of the design easier.
      • The blank working die was placed below the master die.
      • The dies were pressed together with about 20 tons of pressure.
      • The mint workers did not know if the design features transferred correctly. So they would remove the die and inspect it.
      • If the working die did not have a satisfactory impression from the master die, the die was warmed up and placed back under the master die for another impression (stirkes).
      • When the workers placed the working die for a second and potentially other additional impressions, if the die was not correctly lined up it may cause a second impression to be visible.
      • These additional impressions if they were slightly rotated or off on any axis, it caused the additional impressions to be visible and thus called a "doubled die".
      • Once the die impressions were acceptable, the die was inspected.
      • The newly created die (with multiple impressions) was added to a coin press.
      • This working die with the multiple impressions begins to make coins and will transfer the multiple impressions from the die to the struck planchet (coin blank).
      • These coins are typically business strikes and are released in the community where coin collectors find them and report them to the news and coin collecting societies.

      How to recognize a doubled die
      • Doubled dies can be visible on the Obverse or Reverse of the coin, or both.
      • A Doubled die on the obverse (front of the coin) is called a Double Die Obverse (DDO) .
      • A Doubled die on the reverse ( back of the coin) is called a Double Die Reverse (DDR).
      • Doubled dies may be subtle or severe.
      • Doubled dies usually show the doubling at the same height or very close to the same height of the original impression.
      • The features on the coin that are affected by the doubled die may be thicker than normal.
      • The doubled die may exhibit a thin "cookie cutter" style line that indicates where the letters, numbers or features overlap.
      • Doubled dies may exhibit "notching" or an area near the end of a number, letter or device that shows where the doubling ends.
      • Doubled dies typically do not exhibit any sort of damage in the area of doubling. Any damage seen could have been done after the coin left the mint.

      Strike doubling, Machine doubling, machine damage, Machine doubling (worthless doubling) indicators
      • Affected areas with mechanical doubling (worthless doubling) typically makes letters look thinner.
      • Mechanical doubling often appears shelf like, with one area lower than the other.
      • Mechanical doubling is only one coin impression with parts of the letters, numbers and devices removed from damage.
      • Mechanical doubling may exhibit damage going in one general direction ( example from south west to north east) on the coin.
      • Mechanical doubling may exhibit sheering lines in the affected area.
      • Mechanical doubling is often caused when a coin is struck, the die does not clear the coin completely and the die collides with the coin and sheers off some of the letters, numbers or devices.
      • Mechanical doubling does not make the affected areas of the coin look thicker, it actually makes the letters thinner.
      • Mechanical doubling does not show the classic notching nor does it exhibit that "cookie cutter" line that separates the impressions.
      • Mechanical doubling again, may look shelf like, one area higher than the other - a classic sign of machine doubling ( worthless doubling).

      Link to the Video:

      Educational Series: What is Mechanical doubling? How to identify Mechanical Doubling.
      Gary Kozera
      CONECA State Representative for Virginia
      Website: http://www.minterrors.org
      Forums:http://minterrors.org/index.php?/forums/
      Auction House: http://auctions.minterrors.org
      Store: http://minterrors.org/index.php?/store/

      Comment


      • #4
        Originally posted by MintErrors View Post
        This is a classic example of "strike doubling" something went wrong and it damaged the coin. The possibilities are endless how this occurred but the end result as Bob P. has mentioned is that it's a form of damage.

        Have a look at the list I made up which helps with doubled dies:

        Doubled Die (aka Hub Doubling)
        • Doubled Die (aka Hub Doubling) Prior to 1996, the Master die was placed in a high tonnage press
        • A blank working die was warmed up to make the transfer of the design easier.
        • The blank working die was placed below the master die.
        • The dies were pressed together with about 20 tons of pressure.
        • The mint workers did not know if the design features transferred correctly. So they would remove the die and inspect it.
        • If the working die did not have a satisfactory impression from the master die, the die was warmed up and placed back under the master die for another impression (stirkes).
        • When the workers placed the working die for a second and potentially other additional impressions, if the die was not correctly lined up it may cause a second impression to be visible.
        • These additional impressions if they were slightly rotated or off on any axis, it caused the additional impressions to be visible and thus called a "doubled die".
        • Once the die impressions were acceptable, the die was inspected.
        • The newly created die (with multiple impressions) was added to a coin press.
        • This working die with the multiple impressions begins to make coins and will transfer the multiple impressions from the die to the struck planchet (coin blank).
        • These coins are typically business strikes and are released in the community where coin collectors find them and report them to the news and coin collecting societies.

        How to recognize a doubled die
        • Doubled dies can be visible on the Obverse or Reverse of the coin, or both.
        • A Doubled die on the obverse (front of the coin) is called a Double Die Obverse (DDO) .
        • A Doubled die on the reverse ( back of the coin) is called a Double Die Reverse (DDR).
        • Doubled dies may be subtle or severe.
        • Doubled dies usually show the doubling at the same height or very close to the same height of the original impression.
        • The features on the coin that are affected by the doubled die may be thicker than normal.
        • The doubled die may exhibit a thin "cookie cutter" style line that indicates where the letters, numbers or features overlap.
        • Doubled dies may exhibit "notching" or an area near the end of a number, letter or device that shows where the doubling ends.
        • Doubled dies typically do not exhibit any sort of damage in the area of doubling. Any damage seen could have been done after the coin left the mint.

        Strike doubling, Machine doubling, machine damage, Machine doubling (worthless doubling) indicators
        • Affected areas with mechanical doubling (worthless doubling) typically makes letters look thinner.
        • Mechanical doubling often appears shelf like, with one area lower than the other.
        • Mechanical doubling is only one coin impression with parts of the letters, numbers and devices removed from damage.
        • Mechanical doubling may exhibit damage going in one general direction ( example from south west to north east) on the coin.
        • Mechanical doubling may exhibit sheering lines in the affected area.
        • Mechanical doubling is often caused when a coin is struck, the die does not clear the coin completely and the die collides with the coin and sheers off some of the letters, numbers or devices.
        • Mechanical doubling does not make the affected areas of the coin look thicker, it actually makes the letters thinner.
        • Mechanical doubling does not show the classic notching nor does it exhibit that "cookie cutter" line that separates the impressions.
        • Mechanical doubling again, may look shelf like, one area higher than the other - a classic sign of machine doubling ( worthless doubling).

        Link to the Video:

        Educational Series: What is Mechanical doubling? How to identify Mechanical Doubling.
        Thank you! Very informative!

        Comment


        • #5
          I agree with Bob, this coin has some plating issues causing something I will call plating disturbance doubling
          Jason Cuvelier
          CONECA - ErrorVariety.com - Traildies.com - MADClashes.com - Error-Ref.com
          (all images I use are ©Jason Cuvelier 2008-13)

          Comment

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