What Went Wrong -error coins that escaped the Mint

“Wrong Planchet Errors” are coins that are struck on planchets (rimmed or un-rimmed blank) that were intended for other coins, medals, or tokens. They are among the hardest to find errors in the Australian decimal series and being able to purchase several at the same time would be a fantastic opportunity for us. Well, we were lucky enough to be offered a group of stunning wrong planchet errors by an old friend of ours. Of course, we leapt at the opportunity and with the coins now in hand they also could be called “old friends” as we had seen most of them years ago when we helped to identify, classify and photograph them.

In this article we’ll discuss one of the coins we purchased, speculate about the origins of the coin, and draw some conclusions about whether it’s actually an error or not.

Figure 1 – Australian 1976 Proof One Cent Struck on Fiji Silver Planchet

Identifying the Error

FIGURE 1 shows a remarkable coin, a proof Australian 1976 one cent struck on a silver planchet. The coin is just one of two or three errors of this type that are known, and the one shown has been graded by PCGS as PR61CAM. The error is remarkable because it is struck in sterling silver and the first Australian sterling silver decimal coins weren’t struck until 1982! How did this come about? The first clue is to understand that in most years since it opened in 1965 the Royal Australian Mint (RAM) produced coins, tokens, and medals for countries other than Australia. The RAM annual report for 1976-1977 shows the table shown in FIGURE 2.

Figure 2 – Royal Australian Mint Annual Report 1976-77

The 6th line of the table indicates that 3,023 sets of sterling silver proof coins were struck by the RAM for Fiji, all dated 1976. A quick look through our go-to world coin reference, Krause, turns up KM#27a, the 1976 Fiji one cent struck in sterling silver. It’s listed as 17.5mm in diameter, weighs in at 2.26g and has a mintage of 3,023. Interestingly, the diameter of the Fijian coin is the same as an Australian one cent coin. All that information gives us (and hopefully you) the strong indication that the error in FIGURE 1 is indeed an Australian one cent struck on a sterling silver blank intended for a Fijian silver one cent. PCGS obviously agreed with this conclusion as the coin is attributed on the holder as “Stk on Fiji Silver 1C Plan” (FIGURE 3).

Figure 3 – PCGS PR61 Stk on Fiji Silver 1C Plan

How Did This Happen?

The question now is how did this coin actually get made? We’ll never know for certain but it seems fairly clear that this error is the direct result of so-called “Mint Sport”. “Mint Sport” being an Australian term for coins that are deliberately created by mint workers that differ from normal specifications or have the appearance of manufacturing errors. Why do we believe this item is “Mint Sport”?
The primary reason is the manufacture of Australian proof coins is conducted to extremely high standards. Proof blanks are specially prepared, polished and placed into trays that allow each blank to be handled with great care. Those trays are supplied to a dedicated proof manufacturing room where individual workers are responsible for hand loading coin blanks into coin presses and then striking the coin with precision at least twice via the press of a button. The coin is then removed from the press and inspected closely before being loaded into trays prior to packaging.

At this point you have to ask yourself, when workers were producing 1976 proof coins could a silver blank intended for a Fiji proof set have:

1. Somehow contaminated the supply of polished bronze blanks that one cent coins were supposed to be made from.
2. Been mistakenly loaded into a coin tray.
3. Gone unnoticed that it was clearly not bronze when hand loaded into a coin press.
4. Gone unnoticed when inspected after striking and looking different together in the tray of bronze coins.
5. Passed other quality checks prior to packaging.

It seems unlikely that all those mistakes could occur. However, consider that in 1976 security procedures at the RAM were not the same as they are now. A worker could have easily obtained a handful of silver Fijian blanks and struck some coins just before or after a shift started or moved blanks between machines tasked with different jobs. Those same coins were pocketed and taken home as souvenirs and at some later time were sold on. It seems even more plausible when you understand that many other examples of obvious “Mint Sport” did escape the RAM in the mid 1970’s.

Are Mint Sport coins Errors?

The question we must ask now is “are Mint Sport coins actually errors?”. In our opinion Mint Sport coins such as this cannot actually be called errors as they are deliberately created. This is the opinion of some collectors who are scornful of the idea that Mint Sport has a place in their collections. Other collectors don’t allow the dubious origins of such coins to dissuade them and still find Mint Sport coins to be collectable and desirable. One only needs to look at the prices that double obverse / reverse coins from the 1970’s fetch, or the strong online demand for 2007 double obverse five cent coins to know that there is a ready market for Mint Sport coins.

Is There One Other Possibility?

There is another possibility for the origins of this coin. A possibility that could only be resolved by making contact with the RAM and seeking clarification. What if in 1976 the RAM was considering creating a silver proof set for sale in Australia? What if they struck a few test coins from readily available Fijian silver blanks for evaluation? What if a couple of those test coins actually slipped out of the RAM or perhaps were given out as gifts? It’s a tantalising idea and would change this silver one cent from an error or Mint Sport into a trial striking, which is quite a different matter altogether!

Mark Nemtsas and Kathryn Harris own and run ‘The Purple Penny’ coin shop in Adelaide and are passionate about error coins.

References

1. Royal Australian Mint Thirteenth Annual Report 1976-1977. (1978). Australian Government Publishing Service, p.7.
2. Michael, T., Schmidt, T. and Giedroyc, R. (2019). 2020 Standard Catalog Of World Coins. 1901-2000. Stevens Point, Wi: Krause Publications, A Division Of F+W Media, Inc.
3. The Australian Coin Collecting Blog. (2017). 2007 Double Headed Australian 5 Cent Coin. [online] Available at: https://www.australian-coins.com/error-coins/2007-double-headed-australian-5-cent-coin/ [Accessed 7 May 2023].

What Went Wrong -error coins that escaped the Mint

Figure 1 – Australian 1956 florin with ragged clipped planchet error

Clipped planchets are one of the most common errors seen by collectors. Despite this, they can be one of the hardest to understand error types. Frequently we see the new collector crying out “I could just make that with some tin snips!”. Of course, this is often wildly inaccurate. All a collector needs to pick a real clipped planchet error from post mint damage (PMD) is a basic understanding of the coin manufacturing process and the ability to visualise how metal might flow when a coin is struck.

Shown in Figure 1 is a 1956 florin with a good sized ragged or end-of-bar clipped planchet error that weighs just 10.86 grams. When posted on our social media channels this coin generated some heated discussion, with one commenter suggesting it had been “freshly broken” and “clearly hit with a hammer”. Did we indeed post up a broken coin that we’d hit with a hammer? Of course not. Let’s examine the coin in detail and explain why this is a genuine error.

Blakesley Effect

The new error coin collector must understand that many coin blanks are pre-rimmed by an upsetting mill BEFORE they are struck. The upsetting mill (not surprisingly) upsets (raises) the rim of the coin blank. This helps to reduce the striking pressure required to make the coin and to ensure a high, protective rim that helps to preserve the coin design as it circulates. A raised rim is created by running the coin blank under pressure between two metal rollers. However, when the blank is incomplete (as was the case here) no force can be applied opposite the missing area of the coin and strike weakness will be evident. This effect is known as the “Blakesley Effect”, named after the numismatist who first identified it. Figure 2 clearly shows the area of weakness on the rim opposite the missing region of the coin.

Figure 2 – Blakesley Effect

Metal Flow / Fishtailing in Legends

When a coin blank is struck under extreme pressure it essentially behaves as a semi-plastic fluid and will flow along the path of least resistance. This is how the metal of the coin blank “fills” the coin die when it is struck. In the case of a clipped blank the path of least resistance is TOWARDS the missing area of the coin. Metal will flow OUTWARD in the lettering of the dies filling the outside end of the letters. This leaves the inside end partially filled often with a typical “fishtail” type shape. Which gives rise to the name “fishtailing” of the lettering. Figure 3 shows weakness and fishtailing at the base of the letters and numerals “H II D” on the obverse.

Figure 3 – Fishtailing

Gradual Metal Transitions

It seems intuitive that breaking or cutting a coin will result in metal deformation and sharp transitions near the edge of the cut. When a clipped coin blank is struck this is not the case. Transitions from the completely struck up area of the coin to the missing area of the coin are gentle as the strength of strike weakens gradually because there is not enough metal to fill the die. This will be most obvious on the rims around the missing region of the coin and will also be apparent in any rim beads or rim denticles. Figure 4 shows obvious weakness in the reverse rim denticles near the clipped region of the coin.

Figure 4 – Weakness in Denticles

Conclusions

Once the time is taken to understand how a coin is made and how coin metal flows when struck it becomes a reasonably simple task to separate the wheat (genuine clipped planchets) from the chaff (the damaged coins). In fact, often it is possible to pick a genuine error from post mint damage from relatively poor online images once you know what to look out for. If, in your collecting journey you see someone post up a coin with a piece missing make sure you evaluate it carefully before commenting “I could create that with tin snips!”.

Mark Nemtsas and Kathryn Harris own and run ‘The Purple Penny’ coin shop in Adelaide and are passionate about error coins.