Discs Carrying Undersized Coin Designs Arise in Two Ways

by Mike Diamond for CoinWeek…

Planchets and blanks struck by dies belonging to smaller-size denominations are always, or almost always, the result of backroom shenanigans. The same applies to double-denomination errors involving oversized host coins. These sorts of intentional errors are well-documented here and abroad.

Less appreciated is the fact that planchets sporting undersized designs fall into two very different categories. Most are “oversized wrong planchet errors,” produced by inserting a planchet into a press set up to strike a smaller denomination. A smaller cohort consists of undersized two-faced mules. Such errors arise when dies are installed in a press that is otherwise set up to strike a larger denomination. In other words, the collar- and quite likely the feeder mechanism– are designed to accommodate the larger denomination.

While domestic coins featuring undersized designs command hefty, four-figure prices, foreign versions are much more affordable. My most reliable source for coins carrying undersized designs is the country of Malaysia.

Figure 1. This Malaysia 20 sen planchet was struck by a pair of 2005 1 sen dies. It is an oversized wrong planchet error.

Shown here is a copper-nickel Malaysia 20 sen planchet (1989-2011) struck by a pair of 2005 1 sen dies. The slightly uncentered strike is typical of oversized wrong planchet errors. The planchet was presumably inserted between the 1 sen dies by hand. In such circumstances, there’s no incentive or means to achieve a perfectly centered position. The edge of the coin lacks any sign of collar contact, which is what you’d expect. The collar would have been positioned below the face of the anvil die, or if initially deployed, the collar would have been pushed down to the level of the anvil die face by the 20 sen planchet as the latter was forced down by the impact of the 1 sen hammer die. The 1 sen dies show light clash marks. Dies withdrawn from service because of clashing or other damage are often used to create intentional errors.

Figure 2a,b. This 2005 20 sen coin was secondarily struck by a pair of much smaller 2005 1 sen dies. Like the previous coin, there is no doubt that this double-denomination error was intentionally created for the collector market. — Figure 2. This 2005 20 sen coin was secondarily struck by a pair of much smaller 2005 1 sen dies. Like the previous coin, there is no doubt that this double-denomination error was intentionally created for the collector market.

The same procedure was undoubtedly used to produce this 2005 20 sen coin overstruck by 2005 1 sen dies. Again, the 1 sen design is slightly uncentered. The edge retains the reeding generated during the original 20 sen strike.

A more recent oversized wrong planchet error is this nickel-brass 20 sen planchet (2011-2024) overstruck by a pair of 2019 5 sen dies. As expected, the 5 sen design is slightly uncentered and the coin’s edge lacks the reeding associated with the larger denomination.

Figure 4a. Similar in appearance to the previous coin, this coin actually belongs to a very different error category. It is a two-faced mule in which a pair of 2022 5 sen dies were installed in a press set up to strike 20 sen coins. The coin’s edge carries reeding appropriate for the 20 sen denomination. The reverse design is shown in its rotated position relative to the obverse design.

Figure 4b. The edge of the 2022 5 sen on 20 sen planchet.

Although superficially similar, our next coin is actually a two-faced mule. Here, a 20 sen planchet was struck by 2022 5 sen dies within a 20 sen collar. As is the case with other two-faced mules, the undersized design is perfectly centered and the edge shows the reeded edge of a 20 sen coin. The design rim is well-formed on both faces, owing to metal piling up against the collar. The dies are about 135 degrees out of normal medal rotation. Many two-faced mules, along with other intentional errors, show dies that deviate from normal rotation, evidently because the folks producing these clandestine products can’t be bothered with such subtleties.

Figure 5. This Malaysia 10 sen planchet was struck by a pair of 2005 1 sen dies inside a 10 sen collar. It is another undersized two-faced mule. Quite a few identical specimens are known.

I haven’t seen any other mules identical to this one, but two-faced mules from earlier years do exist. Shown here is a 2005 1 sen design struck on a 10 sen planchet within a 10 sen collar. Once again, the design is perfectly centered, the design rim is well-formed (at least on the obverse), and the edge carries 10 sen reeding. The dies show close-to-normal medal rotation. Several examples of this undersized two-faced mule are known. The often duplicative nature of such mules provides another clue that these are not oversized, wrong planchet errors.

There are several circumstances in which the nature of an undersized design would be difficult to discern. An undersized two-faced mule will be difficult to distinguish from an oversized wrong planchet error if the collar is not deployed. In such cases, one of the few remaining clues would be perfect centering. However, a planchet unconstrained by the collar will often be imperfectly centered. Likewise, a well-formed design rim is unlikely to form without confinement by the collar. Under these circumstances, duplicate specimens are unlikely to be produced, encountered, or recognized.

Even if the collar is deployed, a weak strike or a set of dies applied to a much larger planchet may not generate any signs of collar contact. In the latter case, with so little of the planchet under compression, the planchet will not expand enough to contact the collar’s working face. The only clues would then be perfect centering and, hopefully, the presence of more than one identical specimen.

I will conclude this article by noting that not all undersized designs fall into the two categories described above. Some undersized designs represent illicitly applied die impressions. While these die impressions are generated inside the mint, it doesn’t appear that a coining press is employed. Several domestic examples are known, including a proof 1976-S Jefferson Nickel obverse design weakly impressed into a Proof copper-nickel clad Eisenhower Dollar planchet.

Illicitly applied die impressions– whether they’re undersized or not- are variously characterized by the use of Proof dies or planchets, the use of wrong or non-standard planchets, weak impressions, off-center impressions, multiple impressions, peculiar and exaggerated doubling, the presence of faint accessory raised or incuse design elements on one or both faces, designs applied in stages, the use of a single die, mule facsimiles (mismatched dies, including paired obverse or reverse dies), wildly misaligned, tilted and rotated dies, heavily vandalized dies, target discs subjected to heavy pre- or post-impression damage, the presence of weird patterns and textures, and the presence of a nonsense design on one face.

Illicitly applied die impressions are most easily confirmed when Proof dies and planchets are used. When business strike dies and planchets are employed, these mint-sourced monstrosities are hard to distinguish from sloppy counterfeits. (Coin World, November 16, 2020, January 4 and February 1, 2021, August 29, 2022).

Figure 6. This 1887 Peru un sol was counterstamped by a pair of 1894 Guatemala 1/2 real dies. Unlike the previous coins, this secondary strike was sanctioned by the government.

Dies belonging to a small-size denomination can be used for government-authorized counterstamps. Shown here is a silver dollar-size 1887 Peru un sol that was counterstamped by a pair of tiny 1894 Guatemala ½ real dies. The ½ real design was used to convert foreign coins into legal tender in response to an influx of foreign silver after the Panic of 1893. In addition to Peru, host coins include dollar-size silver coins from Brazil, Chile, and El Salvador. Guatemala silver one peso coins were also counterstamped.

Oversized wrong planchet errors and double-denomination errors with oversized host coins appear among domestic coins. The years 1981 and 2000 were particularly productive. Most of the 1981-dated specimens involve a cent obverse die struck into a larger-denomination planchet or coin. However, there is Lincoln Memorial Cent die cap that was fitted onto a 1981-P Roosevelt Dime obverse die for one or more additional strikes. To my knowledge, all the 1981-dated specimens are uniface (struck against an underlying planchet) while those struck in other years are die-struck on both faces. It’s not clear why only obverse dies were used in 1981.

I know of only one domestic example of an undersized two-faced mule – a 2000-P Maryland State Quarter design struck on a Sacagawea dollar planchet inside a Sacagawea Dollar collar. Three specimens have been reported.

In summary, oversized wrong planchet errors will variably show these characteristics:

Less-than-perfect centering.
Little or no development of the design rim.
Lack of a collar-struck edge (no reeding or absence of a smooth, flat, vertical surface).
Instead, the planchet’s trapezoidal cross-sectional edge profile or the cut-and-tear texture of a blank are retained.
Diameter expanded beyond that of an unstruck planchet and, quite often, beyond that of a normal host coin.

An undersized two-faced mule will ideally display these characteristics: