Identifying Die Varieties - Appraising Your Coin Collection
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Copyright 2015 by Kevin Flynn, All Rights Reserved
To make a coin, a tool called a ‘working die’ is used. The die has the incused image of the coin on it. Two working dies are required to strike a coin, one for the obverse and one for the reverse. The coins are struck in a machine called a coining press. A pair of obverse and reverse working dies are placed in the coining press above and below and used to strike a blank disc, called a planchet. The planchet is struck by the dies with thousands of pounds of pressure, pushing the metal from the planchet up into the incused image on the working dies.
The process in creating a working die requires several steps, the critical of which involves pressing the raised image of the design on a working hub into the working die in a machine called a hubbing press. This might require several hubbings to get a good impression into the working die. Sometimes during the die making process, mistakes can be made. These mistakes can make the die look different from other dies and are known as die varieties. All coins struck with the working die will show the variation. Some types of die varieties are very valuable. Some types are very common during certain years. Below are some examples of different types of die varieties.
A doubled die is a coin that has two or more images of the design. There are several different types of doubled dies, which are reflected on how they are created. Below is a picture of a 1955 Lincoln cent with very dramatic doubling seen all around the coin. The doubled die was created when the working die was rotated counter-clockwise in perspective to the image impressed from the previous hubbing, when it was placed back into the hubbing press. This is one of the more dramatic doubled dies for the Lincoln cent series. In perfect condition, this coin can be worth around $15,000.00. There are thousands of the doubled dies on 20th century coins. Many are minor and worth only a little, but imagine finding a monster like the 1955.
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There are other types of doubling that are not valuable such as strike doubling, which occurs when the coin is being struck in the coining press or sometimes when the die wears down. It is important if you want to collect doubled dies to be able to know the difference between a hub doubled die and other types of doubling that are not valuable.
A repunched date occurs when the date was punched into the working die in more than one location. Before 1909, the date was struck into each obverse working die by a Mint employee who used a mallet and a date punch. Perhaps they wanted to get a deeper impression into the die or thought it was too high or low. Many of these repunched dates only show minor signs of extra digits. Some are very dramatic and are valuable. Below on the left is an 1864 Two cent piece with dramatic repunching on the 18. On the right is a photo of an 1864 Two cent piece, which was punched four times showing four different images of the digits.
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A misplaced date is the same as a repunched date, but the repunched digits are much farther away. Sometimes by accident, the digits of the date were punched into the denticles below the date or the design of the coin above the date. There are many of reasons this could happen. Mainly, it is thought that it was caused by inexperienced Mint employees or by misjudgment. Remember the area in which the date is struck is only one-quarter of an inch wide and one-tenth of an inch high. Misplaced dates happened on almost all coin series before 1909. There are no misplaced dates found on coins after 1908 because the Mint changed the way it made dies and no longer struck the date into the die by hand. There are 400 misplaced dates known and new ones being found all the time. Below on the left is an 1870 Indian cent with a bold 0 in the denticles. On the right is an 1847 five dollar gold piece with a bold 1 seen in the neck.
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One of the rarest types of die varieties and sometimes the most valuable is an overdate. An overdate is a coin that shows two dates from different years. Let’s first show what an overdate looks like. The photo below on the left is of an 1887 three cent nickel on which you can see the shape of a 6 under the 7. This working die was first struck with an 1886 date punch, then struck over with an 1887 date punch. The photo below on the right is of an 1918-D Buffalo nickel that shows a 7 underneath the 8.
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There are approximately 200 overdates for all series. Most of these are for 19th century coinage. There are fewer than 10 overdates known for 20th century coinage. Overdates are one of the more collected and enjoyed type of die varieties.
A mint mark is used to identify which Mint a coin was struck, for example, ‘O’ for New Orleans. Up until around 1990, the mintmark was struck into each die by a Mint employee with a mallet and a punch with the mint mark at the end. If the Mint employee thought the first punch was too soft, too high, or too low, then he might strike the mintmark again into the die.
A repunched mint mark (RPM) is a coin that shows two or more mint marks punched into it. These are common for 20th century coinage, especially for Lincoln cents. There are more than a thousand repunched mint marks known for the Lincoln cents alone. Some of the more dramatic repunched mint marks can be very valuable. In the photo below on the left, a totally separated D can be seen on this 1956-D Lincoln cent. The photo on the right is of a 1942-D Jefferson nickel, in which the D is punched over a horizontal D.
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An over mint mark (OMM) is a coin that shows two or more different lettered mint marks. The photo below on the left shows a 1944-D Lincoln cent with an obvious S underneath the D mintmark. The center photo shows a close-up of the 1944-D/S cent. The photo below on the right shows a 1938-D Buffalo nickel with an obvious S underneath the D mintmark.
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Over mint marks are rare with about 50 known for all series. These are highly collected and sought after.
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Copyright 2015 by Kevin Flynn, All Rights Reserved
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