|As a continuation of the collecting of mint error coins from Issue #6, we move to the more dramatic examples which have in some cases mysteriously found their way out of the United States mint.
Mint error coins continue to be exceedingly popular, and finds among the current year's population are virtually non-existent. This is due to the fact that the Mint has become far more efficient in their filtering techniques and employee monitoring. For example, coins had been counted at banks, where counting machine jams often resulted from error coins that had slipped through the Mint's inspection process. Now, however, coin is run through counting machines within the Mint to catch virtually all mistruck items. This can only mean a smaller supply for growing demand.
One important note...double-headed or -tailed
coins are virtually all manufactured away from
the mint and are not errors. They are produced
from two coins ground and soldered together
and are used to win coin tosses. They are available
in magic shops for a few dollars, but have no
What follows are a few examples of highly
unusual errors that government eyes and machinery
| Triple Struck Coins
eye appeal of the multiple strike error
coin has made it one of the most sought
after types. The more obvious the encroachment
of the second and third strikes on the first
strike, the greater the interest. More often
than not, though, multiple strikes appear
as almost shadows of previous strikes, being
very close together due to the high speed
machinery. What makes this type even more
desirable is the appearance of more than
one date, as well as the presence of the
reverse image on the strikings (in lieu
of uniface strikes, which are more common).
The example at left is a recent Jefferson
nickel that clearly has two additional strikes,
one 75% off-center, and the other 90% off-center.
The strikings are also referred to as DSBS,
or Die Struck Both Sides. Distortion of
the initial strike is evident from the additional
strikings, partcularly on Monticello.
| Capped Die Coins
A capped die is simply a coin that for some
reason sticks to the upper die during striking,
and through multiple strikings thins out and molds around
the top or obverse die, forming a cap similar
to a bottle cap or thimble. The greater the number
of strikes, the higher the cap metal will
be pushed around the upper die shaft.
The cap error coin is an extremely spectacular
error type which is quite scarce and virtually
unavailable in larger denominations due
to their smaller mintages.
The present example is the plate coin on
page 214 in The Error Coin Encyclopedia.
It is a 1970 Denver minted cent that is
particularly deep from numerous strikings,
and having the reverse design virtually
obliterated. Although deep die caps often have damage due to splitting off from the die, this specimen has nearly perfect facing and rims.
| Off-Center and Cupped Coins
the best known error coin type is the off-center.
No two off center strikes are ever identical.
The off center error occurs when the blank
falls in a random manner so that it is partly
off the lower die just prior to striking.
Generally, the larger the coin, the more
chance there is of the coin cupping, or
bending when the die strikes. This creates
a more dramatic appearance.
The example is a 1964 Kennedy half dollar which was struck 70% off center and cupped. The strike is exceptional, and indicative of fresh dies. This particular item is rumored to have been in the personal collection of a mint official who was employed with the mint at the time.
| 3-Piece Bonded Set
||Bonded coins occur when there is a major disruption of the planchet feeder system for the coinage presses. If the struck coin is not ejected properly and another planchet is fed into or near the same collar, part of that struck coin will land on top of the previously unejected strike. The two coins may be crimped and subsequently bonded together. If this process repeats, more will join in the bonding.|
Bonded coins rarely escape the mints, except through the shipping of bulk, uncounted but weighed coinage, or with the assistance of an unscrupulous mint employee. Recently, the Secret Service has determined that those bonded sets of more than three coins are subject to confiscation, due to the fact than most are from clandestine release.
The specimen at left is a three-coin bonded set of 1990 Philadelphia minted cents. These items are exceedingly fascinating to view.
| Double Denomination Coins
||Another very dramatic mint error is a coin struck on a previously struck coin. An example of this type would be a cent struck on a previously struck dime. Here, we will see elements of each design on the struck coin.
The wrong planchet error occurs from the use of older "tote bins" which are used to carry the blanks and struck coins from place to place. These are large steel tubs with sloped bottoms which allow the emptying of the bin completely when a slide trap door is opened. Occasionally, a blank or struck coin will remain stuck in the crevices of the bin and escape unnoticed. Later, when that particular bin is used to carry other struck coins, the trapped piece will be dislodged and mixed with the rest of the contents. Thus, double denominations happen.
The coin displayed here is a 1996 dime which was later struck with cent dies. These double denominations tend to be the most common and least expensive of this error type, though they still command $400 to $700, depending on the date and grade.
Photography by Gary Le Blanc
the mix of a horse and donkey, a mule in
coin errors is an unlikely combination of
two incompatible entities: a different denomination
from mismatched dies on each side. Although they
are not uncommon in European and Asian coinages,
the appearance of these in the U.S. is very rare,
mainly because the different denominations
are of differing diameters, so dies are generally incompatible.
Recently, however, several mules have come
to light. One which has received quite a
bit of press is the Sacagawea dollar
planchet and reverse/ Washington quarter
obverse. 10 to date have made their
appearance in the East and Mideast United
States beginning in mid-2000. (Frank Wallis,
the finder of the discovery, or first piece,
had contacted Studium for information on
its origin and authenticity. Pardon my momentary
Another mule of which only two have been
discovered is a Lincoln cent planchet and
obverse/Roosevelt dime reverse. One is dated
1995, the other 1999. Due to their extreme rarity, documented prices realized for this type of error have ranged from $25,000 to over $80,000.
The Error Coin Encyclopedia - Third Edition
Margolis-Weinberg - 2000