The rarest form of the clipped planchet error is the elliptical clipped planchet or elliptical planchet error coin. This unusual type of clipped planchet error occurs (just like the other clipped planchet errors) during the manufacture of the blanks for coin manufacture. It’s called a an elliptical clip due to the shape of the resultant error coins, one of which you can see below, an impressive 1961 shilling with a distinct elliptical shape.

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How does this sort of error occur? One must think about how the blank manufacturing process occurs, in the case of this shilling the silver strip runs through a blanking press and metal tools punch out disks of silver that will me made into coins. In between punching operations the strip moves along, and stops ready for the next blanks to be punched out. However, what happens if the strip doesn’t move along far enough when the next blank is punched and the blank that was just punched doesn’t detach properly? We’ve done our best to explain this in the image below:

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In this image the first coin blank punching operation is the blue disk, and for whatever reason, when the metal strip moves along under the punching press after the first punch it does not move far enough and the coin blank does not leave the strip. When the next coin blank punch occurs (the green disk) it happens OVER the blank that is still sitting in the metal strip. This forms a crescent shaped clipped planchet on both edges, and an elliptically shaped planchet in the middle. It seems likely that the crescent shaped clips do not make it through quality control because they are so small, whereas the elliptical planchet does. And of course a coin is struck on it and the elliptical planchet error coin is formed.

1921 Half Penny Struck on Elliptical Planchet

To the new collector it may not be immediately obvious how to distinguish a real elliptical clip error from a coin that someone has either cut or ground to shape. Well, as it turns out, the same techniques we’ve described to determine a real clipped planchet error can be applied to elliptical clipped planchets. Both elliptical clips shown in this article show fish-tailing of the legends near the missing regions of the coin, plus both have extremely poorly formed obverse rims. Both of these factors indicate that they were struck on incomplete clipped planchets, rather than being entire coins that were somehow trimmed down later.

19xx 2 Cent Double Struck Error

197x 2 Cent Double Struck Error

The eye candy for error coin collectors today are these two double struck Australian two cent pieces. They were struck once normally and then struck again after failing to exit the press in a timely manner. These coins are lovely collectable examples of off-centre double struck errors. As they are grossly misshapen these error coins would never have left the Mint in a roll, most likely in a mint bag or an employees pocket at a time when little value was put on error coins. The Arnold Machin portrait used from 1966 to 1984 dates these coins to within that time with one coin showing a 7 indicating it was struck in the 1970’s. It’s not possible to determine the Mint of origin because of the error. Both coins have endured the same experience, let’s look at the coin from the 1970’s in closer detail.

It all started with a regular struck coin. The main strike is quite normal with no interesting features. The partial strike off the edge of the coin is another story. This occurred after the coin failed to eject from the press and was caught on the edge and struck (partially) with a second strike. This was likely due to a press malfunction. The edge of this second strike is out of round indicating it wasn’t held by the collar and metal flowed upward (inward). This is confirmed by prominent fishtailing and thinning of the lettering II and AUST as again, the metal flowed upward during that second strike.

Those that may be confused by this type of error we’re still looking at a single (normal weight) planchet and not somehow a joining of two coins, extra metal piece or an overweight planchet. The partial second strike has been struck over the existing metal obliterating the original strike.

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This is the first of what we hope will be a regular feature where we look at a few of the most interesting error coins available to Australian buyers via eBay auctions or BIN listings.

Australian 1962 Partial Collar (Ramstrike) Florin

We’re very partial to partial collar errors (heh see what I did there) and this 1962 florin is better than most. Usually these coins circulate for a long time resulting in the non-protected side of the coin being heavily worn, scuffed and even scratched. The obverse of this florin is a decent grade, showing slight circulation wear only while the reverse, being partially protected by a high lip (typical of a ramstrike) looks very nice indeed. Of particular interest to the new error collector is the characteristic double rim around the bottom half of the coin showing where the coin blank only partially engaged with the collar die before being struck.

View the 1962 Florin Partial Collar on eBay

Australian 1989 $2 Clipped Planchet Error

It’s always unusual to see a clipped planchet error on an Australian Aluminium Bronze coin. The 1989 $2 in this eBay auction is a lovely example of the type, showing a decent sized curved clip at the very top of the coin. The error also clearly shows one of the signs of a genuine clipped planchet error, namely a strong Blakesley effect at the bottom of the coin opposite the clipped area. The images of the error are good enough to suggest the grade of the coin is decent too, perhaps even uncirculated. One comment I have to make is that it’s always funny to see people placing a whole coin into the clipped region to somehow prove that the error is genuine. This is of course the wrong thing to do, the clipping of the planchet occurs BEFORE it is struck and it’s quite possible for the clipped region to deform during the striking process so that a whole coin no longer fits in the gap, and that doesn’t stop the error from being a genuine one.

View the 1989 Clipped Planchet $2 on eBay

Australia 1966 1c Struck on Incomplete Planchet

The seller of this 1966 1 cent has described the error incorrectly as a ‘pinched planchet’ which is an older description of a small clipped planchet. In actual fact, this coin has been struck on an incomplete and likely underweight planchet. The reverse shows what appears to be a large planchet flaw on the left side while examination of the obverse area opposite shows the design was not fully struck up. What does this indicate? That the missing part of the coin was missing when the coin was struck, and because of that the obverse design opposite was not fully struck up. This error is the same type as this 1966 2c on an incomplete planchet that we wrote about recently. The images of the coin in this eBay sale suggest the grade is fairly good, perhaps with some remaining lustre and mint red.

View the 1966 1c on an Incomplete Planchet on eBay

Disclaimer

Information provided in this article is our opinion only on the coin depicted in the images shown in the eBay listing. It is not an endorsement of any seller and any purchase our readers make through eBay is at their own risk and adheres to eBay’s terms and conditions.

We’ve written quite a few articles recently on coin errors and thought it would be worthwhile to collectors for us to merge two seemingly similar error types to identify and discuss their differences. This will help you recognise each error type and correctly annotate each in your collection.

Below we have two Australian 5 cent coin errors with design details missing. To determine the type of error coin we must look closely at the missing design and any patterns of missing details.

The MOST important thing to note here is you must look at BOTH sides of the coin to make an accurate assessment of the error type.

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If you’ve seen our previous error coin articles then you are one step ahead! Let’s take a close look at each coin above. The top coin has a similar pattern of missing design on both faces of the coin. It’s uniformly weak and has no details towards the outer parts of the design but is perfectly struck right at the centre. The bottom coin is totally different on each side of the coin. The reverse is a normally struck coin, you wouldn’t look at it twice, but the obverse lacks detail in the legends less so through AUSTRALIA and more so on the left of the coin.

So what conclusions can we make here? The bottom coin was struck at optimal striking pressure as there is no fault on the reverse. The obverse lack of detail is due to something being on the planchet surface in an uneven distribution at the time the coin was struck. In this case it was most likely oil or grease from the maintenance process. The top coin was struck with lower pressure than usual because of the uniformity of the missing design. This low pressure affected the entire coin in the same way.

Have you correctly identified the error coins in your collection?

˙ןןıɟ ǝıp puɐ ǝʞıɹʇs ʞɐǝʍ sǝןɔıʇɹɐ snoıʌǝɹd ɹno uı ɹǝʍsuɐ

2002 5 Cent Strike Through Error

Today’s spotlight is an example of the type of error seen quite often on circulating coins although not usually seen to the extent that we see on the example pictured. Shown here is a 2002 5c with the obverse weakly struck around the legends and the reverse a normal strike. The coin is the correct weight of 2.85g so there is no planchet metal missing, if there was metal missing we would conclude that this error was something other than what it actually is. The obverse strike weakness is caused by an excess of oil or grease on the die surface when the coin was struck that obscures the details in the design. It’s likely the press operator wiped the die with an oily rag and it left oil in the legends and some of the tiara and hair detail.

This error is called a strike though or struck through or struck through oil error. A strike through means something was between the die and the planchet when the coin was struck and there are a number of things that a coin can be “struck through” including cotton from a rag, wire, a piece of planchet and in this case oil or grease from the maintenance process.

This coin appears to have a reasonably uniform amount of strike weakness around the legends which could indicate it was struck with a lower than optimal striking pressure. So why have we not concluded this coin is a weak strike or die adjustment strike error? There are 2 tell-tale signs this is not the case.

1. If it was then both sides of the coin would be affected in the same way (which they are not), there is no strike weakness or design missing from the reverse.

2. While the oil affects the obverse legends it isn’t uniform around the whole coin with AUSTR only minimally affected by the oil and ELIZABET is unrecognisable where the oil was the heaviest.

Grading to Extremely Fine this coin has likely been pulled from circulation quite early on and put aside by an eagle eyed collector.

1966 2 Cent Struck on Incomplete Planchet Error

This 1966 2 cent struck on an incomplete planchet gives the collector some very interesting insights into the coin manufacturing process. Firstly though we’ll examine the error itself. The coin is a 1966 2 cent from an uncertain mint (see here for 1966 2 cent mint marks) that has been struck on an incomplete planchet. We know it is an incomplete planchet as it weighs just 4.80g which is about 7.5% less than the expected weight of 5.18g. Clearly the missing part of the coin is on the reverse between about 12 o’clock and 3 o’clock extending a few millimeters into the reverse and about 1mm into the surface of the coin itself. The coin is a glossy red brown as are the corrugated surfaces of the missing part of the coin. Readers with a keen eye will note an area of strike weakness on the obverse. The top of the portrait is smooth and missing a lot of detail and the TH II of the monarch’s name is completely missing.

Could this coin have perhaps been struck on a complete planchet that split into pieces after it was struck? Or perhaps this is a coin that was simply damaged after it was struck? Well, the weakness on the obverse is the key indicator that neither of those cases is true, and that the coin was actually was struck on an incomplete planchet. When the region of the coin opposite the missing area was struck there was a major factor in play that stopped that area being struck up properly. Namely that there was no resisting pressure from the reverse die when the obverse die struck as the planchet in that area of the reverse die was missing! Obviously this will lead to a localised area of low striking pressure and this is evidenced by the weak strike and missing design details on the obverse.

Obverse and Reverse Detail

As an error collector this should teach us an important lesson that can be applied when examining error coins that have parts of the planchet missing. If we suspect the coin was struck without part of the planchet in place, look for an area of corresponding strike weakness opposite the missing area. If there is no strike weakness perhaps the parts of the planchet parted ways AFTER it was struck or you’re simply looking at a damaged coin.

There’s another part of the coin manufacturing process we can learn about by examining the surfaces of the missing area of the coin. There are two things to note. First, there are clear parallel lines traversing surfaces. Secondly, the surfaces themselves, while textured, are still largely smooth and glossy. To understand what we’re seeing here we need to think back to method used to form coin blanks. Basically they are punched from a strip of metal by a machine called a blanking press. The strip of metal is formed by rolling metal between rollers that are progressively closer and closer together until strip of the desired thickness and width is achieved. Of course any piece of foreign metal on the surface of the strip is going to be flattened and pressed into the surface of the strip and elongated in the direction that the metal is rolled. The surfaces of the strip and foreign material are going to rub against each other polishing each surface and extrusion lines are going to form in the direction of rolling. Which, is of course, what we’re seeing here.

This 1966 2 cent struck on an incomplete planchet is a lovely grade, uncirculated and glossy brown. Nearly 10% underweight we have seen that it was struck with part of the planchet missing, and most likely the missing part is due to a metal inclusion that was rolled into the coin bronze prior to the manufacture of coin blanks. That inclusion fell out sometime between the bronze being rolled into a strip and the coin blank being struck. Initially not visually spectacular, this error is of great interest and has some lessons to teach any error collector.

1966C 20c – Broadstruck Out of Collar Error

Today’s error coin spotlight sees us looking at a spectacular broadstrike 1966 20 cent that was minted in Canberra for the release of decimal currency in 1966. How do we know it was minted in Canberra? The RAM somewhat sneakily included non-obvious mint marks in the design of the new decimal coins, which in the case of the 20 cent were minted in both Canberra and London. These mint marks didn’t become generally known until after the release of the new coins but we know quite well what the 1966 decimal mint marks are now. In the case of the 20 cent we need to look at the reverse of the coin on the right side of the duck-billed platypus head where the water swirl ends.

1966 20 Cent Mint Mark Detail – No Gap

In this case the swirl clearly ends at the head with no gap indicating that this 20 cent was indeed minted at the Royal Australian Mint in Canberra. Now that we’ve determined the origin of the coin let’s look at the error.

The coin itself has been struck with no engagement with the collar die at all and while the coin blank was about 3mm or 10% off center. This has resulted in the design being (not surprisingly) 10% offset from where you’d expect it. Classifying the exact type of error is a matter of some debate among collectors. We can definitely say it’s been struck out of collar, in addition the planchet is a millimetre or two larger than a normal 20 cent, so it’s been “broadstruck”. The error is definitely a “broadstrike outside of the collar”. However, is it an “off centre” error? The authors of this blog define an off centre error as a coin being struck far enough off centre that some of the design of the coin is missing. In this case none of the design is missing, so despite this coin clearly being struck off centre it does not fit the strict definition of an off-centre error.

Being struck completely out of collar and “broadstruck” the planchet of this coin was free to flow radially outward when struck. Of course this made the coin itself bigger than a standard 20 cent, and it also resulted in changes to the design of the coin as the metal flowed in an unexpected direction. If you’re a frequent reader of this site you’ve probably read the term “fish tailing” multiple times, and that “fish tailing” is one indicator of unconstrained radial metal flow on a coin. Well, this 1966C 20c broadstrike error has about the best fish tailing of the obverse legends that we’ve seen on a coin. You can see how the word ELIZABETH has been affected below:

Detail of Fish Tailing

Note the V shaped indentations at the bottom of the upstrokes of the letters forming the characteristic “fish tail” shape that gives this phenomenon it’s name. This happens as the metal flows outwards in the incuse die elements that form the letters of the legends. Metal in the middle of the upstrokes flows more that that on the outside presumably due to friction with the die surfaces, similar to how a river’s water flows faster in the middle of the river compared with the water near the banks. The difference in the amount of metal flow leads to the fish tail shapes we can clearly see.

This error is a spectacular example from the first year of issue of Australian decimal currency. It was clearly found prior to circulating as it is a lovely uncirculated grade. It has experienced some poor storage at some time during it’s 60 year life as it’s got some sort of PVC or perhaps adhesive adhesions and would benefit from some sort of appropriate restoration by someone with the correct certain set of skills. Despite that, it’s still an amazing coin and hard to improve on if a collector was looking for a 20 cent error to take pride of place in their collection.

Undated 1966-1984 5 Cent Weak Strike Error

The error coin pictured above in today’s error coin spotlight is a very nice example of a die adjustment strike, weak strike or touch strike Australian 5 cent piece. These are all names used for this type of error coin. We can see the central part of Stuart Devlins’ echidna design and the same of the early Arnold Machin portrait of Queen Elizabeth II. This dates the coin somewhere between 1966 and 1984.

Generally this type of error coin is created during the setup process of a die pair while press operators are dialling in the correct striking pressure at the Mint. It can also happen if there is a malfunction in the press and a lower than desirable pressure strikes the coin.

It is distinctly different from a coin that is for example struck through oil as both sides of the coin are uniformly weakly struck in the same areas. It is also the correct weight at 2.81 grams within the tolerance of the specification of an Australian 5 cent (2.83 grams). This is important if the coin is underweight then the error may have occurred due to lost coin metal which is most often post mint damage (PMD) and not a genuine error coin.

This genuine error coin from the Royal Australian Mint has seen some circulation and would grade to Extremely Fine and is a lovely example of its’ type.