1973 D Lincoln Cent Recurring Die Subsidence Error Stage Progressions

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After the production of the famous 1955 Lincoln Cent Die #1 doubled die variety with an extremely strong spread to the doubling, the Mint took measures to prevent such widespread doubled dies from ever happening again. They placed lugs around the rim of the dies and hubs so that the images on the hub and partially completed working die would align properly when they were placed in the hubbing chamber. These lugs were raised on the working die and they were depressed indentations on the working hub.

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This photo illustrates a working hub that was created for the Lincoln Cent reverse. If you look carefully, you can see that the images on the face of the working hub are raised and look just like they will appear on the struck coins. The arrows point to grooves along the edge of the hub. The lugs on the working die will fit into these grooves to allow proper alignment of the working hub and the working die when more than one hubbing is needed to complete a satisfactory image on the hub or die being made.

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This is a working die (left) for the reverse of the Lincoln Cent as it appears after being hubbed. Notice that the design is reversed from what you will see on the struck coins. Though difficult to see in the photo, the design is depressed (incuse) in the working die. Arrows point to the raised areas (lugs) around the rim that align to the grooves of the working hub. To the right of the working die we can see some more blank steel rods that can be used to make master dies, working hubs, or working dies.

In 1969 the Mint modified the obverse design for the Lincoln Cent. As a result of those changes, they experienced difficulty in getting satisfactory impressions in the working dies. To remedy the problem they removed the lugs from the hubs and dies to allow for deeper penetration of the hub into the die. This did fix the problem and allowed the deeper penetration of the hub into the die, but it opened up the possibility of doubled dies again being created with strong spreads.

It didn't take long for the consequences of this decision to be felt. In 1969 a major doubled die was produced for the 1969-S Lincoln cents. Another major doubled die was produced for the 1970-S Lincoln cents. Several doubled dies found their way into production for the 1971 Lincoln cents with two major varieties known for the 1971-S proof cents. The dam broke in 1972 and several doubled die varieties were produced for the Lincoln cents from all three Mints including a major doubled die for the obverse of the P-Mint cents. During this period of time significant doubled dies were being produced for other denominations as well. After the flood of doubled die varieties in 1972 and all of the publicity that they generated, the Mint returned to the practice of placing the lugs around the hubs and dies.