The Classification of Australian Coin Types
Since the advent of currency coins have reflected the progress of a nation, revealing in their designs and composition the politics and commerce of the society they support. Therefore it was important that the new Australian coinage was recognisable, consistent and trusted.
The need for a new Australian currency arose on January 1, 1901, when the six separate British self-governing colonies of New South Wales, Tasmania, Queensland, Victoria, South Australia and Western Australia came together to form the Commonwealth of Australia. However, it was not until 1910 that circulating British coins began to be replaced by the first Australian silver threepences, sixpences, shillings and florins, followed by halfpennies and pennies in 1911. The first national bank notes introduced in 1910 were a stop-gap issue of superscribed private bank notes which were replaced by new Commonwealth Treasury bank notes in 1913. But it took longer for a national coinage to take hold, and surveys of hoards put away in the early 1920s show that up to 30% of circulating coins were still British.
|1901-dated letter concerning Australian coinage signed by Edmund Barton, the first prime minister of Australia
Click images to enlarge
The London branch of the Royal Mint created all the original master tools (hubs and dies) for the Australian Commonwealth coinage and was also responsible for striking most of its coins until 1915. To meet demand it also supplied master tools to the Heaton Mint and the Calcutta Mint, which were contracted to strike coins for some years before its branch mints in Australia were able to take over full production. Even the emergency dies created by the Melbourne Mint in 1919 and later, during World War II, by the Bombay, San Francisco and Denver mints had their genesis from master tools originally supplied by the London Mint.
Traditionally, a new coin began as a large scale plaster model in relief which when reduced by a pantograph to a steel hub created a real size positive image of the intended design. From this hub a master die with a negative image is struck and defining detail such as edge denticles is added. From the master die more working hubs, and eventually working dies, are produced which theoretically should provide a consistent design for the entire mintage. However, if all or part of this process is repeated then more than one master tool can result, with the possibility of noticeable design changes. Intentional alterations are often required and relief detail can be removed from a hub, and a new master die created. For example, at least the last digit of the date is manually removed and re-entered onto a master die if required for a new year's production. The new date and other mint-generated changes, such as mint marks, can be made to a master die or, as a one-off, to a working die so small positional changes to this detail or even omissions can occur.
The Australian mints had already changed dates on dies for Imperial gold coins, but it was not until the 1924 issues that the Melbourne Mint 'officially' attempted this process on Australian Commonwealth coins when it added a '4' to the dies of all the copper and silver denominations. This proved not to be always a straightforward operation and in some years overdates sometimes resulted when the original figure was not completely removed from the hub and traces of it showed through around the new date on subsequent dies.
Traditionally the London Mint did not mark its own production when striking coins, but usually added mint marks to the working or master dies provided to its branch mints or private mints which it sub-contracted to complete coin orders. However, by 1919 it was decided that the branch mints in Australia were now capable of striking its entire coinage, and so the dies provided to Sydney (halfpenny) and Melbourne (penny) bore no identifiable mint marks. Consequently in 1919, the Melbourne Mint, which was regarded as Australia's senior mint produced its first pennies on un-marked working dies provided by the London Mint, ie the 1919 'Plain' Penny, while Sydney struck the halfpennies also on un-marked dies.
The Melbourne Mint soon exhausted its supply of dies and as an emergency measure decided to use a pair of working dies to produce a master hub and then a master die from which it derived a further supply of working dies. This accounts for the later production of pennies bearing a small dot below the bottom reverse scroll, ie the 1919 //. Penny, a mark to distinguish the additional work on the dies claimed by the Melbourne Mint. Melbourne had been striking all the silver coin denominations since 1916 on dies supplied by London with an 'M' mint mark, but the application of a dot to the 1919 Penny reverse die was the first time in the Commonwealth series that the Melbourne Mint had sought to distinguish the production of coins from dies to which it laid some claim. It is also apparent that during the process of producing a hub and consequently a master die from a used working die, the Melbourne Mint needed to tidy up the fine detail on the reverse legend adding its own distinctive flourish. The altered legend, which can show either strong or slight curvature to the base of the letters, appears on some penny and halfpenny dates during the 1920s and 1930s and is noted in the coin types in the Benchmark Catalogue by an 'm' after the original source die. For example, 'Bm' (indicating a Birmingham die altered by the Melbourne Mint). From 1919 onwards, there is also some evidence that the Melbourne Mint also worked on the obverse dies, as in some years slight curving of the letters in the legend can be observed. These small changes to the obverse dies have not been catalogued, because unlike the dated reverse dies that quickly became obsolete, obverse dies could be used over a long period making them very difficult to classify.
In July 1920, the Melbourne Mint sent three pairs of 1919-dated working dies to the Sydney Mint so it could prepare for the ceremonial striking of its first penny in October of that year. These were experimental dies that were lightly used to test the presses for the 1920 Penny production and the reverses were marked with an additional dot above the top scroll to distinguish their production from the Melbourne minted 1919 //. Penny. The obverse dies were of the English type, the only ones held by Melbourne at the time. The 1919 .//. Penny that resulted is a scarce coin with perhaps a mintage of around 25,000 and marks the first 'unofficial' Sydney-struck penny. Records show that the 1919 .//. reverse dies were destroyed in 1924.
One of the great conundrums of the Australian Commonwealth series is establishing the number of varieties of the 1920 Penny and determining the mints where they were made. Records show that in August, 1920 the Melbourne Mint received 20 Indian obverse dies and 20 Calcutta reverse dies via the Calcutta Mint of which 17 pairs were forwarded to the Sydney Mint so that it could strike its first pennies. The Melbourne Mint had assigned to Sydney the /./ mint mark to distinguish its production, and the vast number of coins eventually struck on the dies provided were of the 1920 /./ variety.
Sydney struck its first 'official' penny at a ceremony held in early October, 1920. In the 1921 publication Australasian Tokens & Coins, the reknowned author Dr Arthur Andrews assumed that this was a 1920 /./ Penny, but it is more likely that the reverse die used was a 1920 'Plain', ie with no mint mark, as it would have been inappropriate to present dignitaries with coins bearing a mint mark not authorised by the London Mint or the Australian Treasury. The rarity of the 1920 'Plain' Penny in high grade suggests that only one plain reverse die was employed in order to demonstrate the presses. It is likely that the better examples which have survived were souvenired by those in attendance at the ceremony, with some retained for institutional collections. In 1996, a specimen-strike 1920 'Plain' Penny reputedly from the collection of A.M. Le Souef, who overseered the closure of the Sydney Mint in 1926, was sold by Noble Numismatics (Sydney). A coin of similar appearance was sold by a Sydney dealer in 2013, which also came from an old Sydney collection, and another discovery, also in 2013, of an early specimen-strike found in a contemporaneous Sydney collection (which PCGS have graded PR64 RB) alongside three uncirculated 1920 /./ pennies, seems to lend considerable weight to this theory.
The usual practice was for production to continue until a die was exhausted, and perhaps another 50,000 coins were struck making their way into circulation. Paradoxically, the 1920 'Plain' variety has long been considered a common coin in low grade, but on closer inspection almost all examples in average circulated condition are found to be the very common 'Melbourne' 1920 //. Penny struck on a filled die. Although not as pronounced as on the 1919 //. pennies, the 1920 //. 'Indian -die' pennies show slight curving to the base of the letters in the reverse legend. The curved lettering does not occur on any of the other 1920 penny varieties, and so, if it is evident on the 1920 'Plain' Penny in your collection, then unfortunately it confirms that your coin is in fact a 1920 //. Penny struck on a filled die.
In November 1920, the Melbourne Mint sent 12 sets of experimental dies to Sydney so it could gear up for the main production of the 1920 /./ Penny. It received three reverse dies struck on 'Calcutta' steel blanks and nine made from 'Melbourne' steel. According to anecdotal reports, the finished reverse dies were marked by Melbourne with a combination of dots to identify both the origin of the steel used in the die production and the mint (Sydney) at which the coins were to be struck. In theory it would be possible to distinguish the production from each die combination. There is evidence that just 146,160 coins were struck on these experimental dies and this figure must have also included the unrecorded production of 1919 .//. pennies. Many believe that this early attempt to single out mint production was quickly abandoned and it is impossible to determine how many of each variety were struck and where. But if the Melbourne Mint had gone to so much trouble to mark the dies, it seems unlikely that the experiment was not pursued, and simple logic seems to offer a credible distribution.
The Melbourne Mint claimed the //. mint mark on the 1919 //. Penny and used it exclusively on the 1920 //. Penny. The .//. mark had been assigned to the Sydney Mint when it was provided with the experimental 1919 .//. dies. This protocol having been set, it can be safely assumed that the 1920 .//. Penny is a Sydney-strike, and on the numbers found it is likely that it was these dies which were predominantly used to calibrate the presses for the main production of the 1920 /./ pennies. All 1919 pennies struck by the Melbourne and Sydney mints had English obverses, and so both mints had access to the dies needed to produce the small experimental runs of 1920 //. (Melbourne) and 1920 /./ (Sydney) pennies with this obverse. In November 1921, the Perth Mint requested dies from Melbourne so it too could experiment with penny production. However, it was the Sydney Mint which responded to this request, sending two sets of 1920-dated dies which, on balance, probably had the .// mint mark. It seems logical that the Sydney Mint would follow the Melbourne lead in passing on this mint mark to Perth, so its coins would be readily identifiable. A mint worker at the time is reported to have had a vague recollection of a Perth mark, and as the .// was the only assignation not claimed exclusively by either the Melbourne or Sydney mints, the 93,600 coins struck at the Perth Mint were more than likely the 1920 .// Penny.
This accounts for the seven accepted varieties of the 1920 Penny and offers strong evidence as to where they were struck.
Of course, variety collectors will continue to offer counter theories. One strongly promoted is that all the 1920 penny varieties, except the 1920 /./ 'Indian' obverse Penny, were struck by the Melbourne Mint. The thinking behind this idea is that examples of the 1920 .// Penny, the 1920 Plain Penny, the 1920 .//. Penny and the 1920 //. Penny were displayed at a numismatic society meeting in Melbourne in November, 1920. However, the more likely explanation is the Melbourne Mint tested the dies for the reverse varieties it had manufactured, including those sent to Sydney, and it was from these trials that examples were displayed. Significantly no examples of the 1920 /./ Penny with an 'English' obverse were found in a 1985 survey of two hundred 1920 pennies held in the museum collection of the Melbourne Mint, which had been originally selected to display die variatons. This concurs with our theory that this variety was Sydney-struck and that the Melboune Mint was probably unaware of its existence.
Other collectors rely on die markers to theorise about the Melbourne, Sydney and Perth strikes of pennies from the early 1920s. What is certain is that both the Sydney and Perth mints were using the same underpowered gold presses until 1922, probably with similar results. Sydney at the time was also striking halfpennies and so would have rotated dies regularly to meet pending orders. The commissioning and decommissioning of the dies left them open to being latterly marked, while the interruption to production meant that dates of coins may have been struck on different pressure settings. Additionally, the Melbourne Mint had light presses as well as the heavy presses it commissioned in 1917 (which were likely used to strike the larger and more robust bronze coins) and it is known that steel blanks from both Calcutta and Melbourne were used to make dies, which could also have affected strike. The outcomes are numerous, so to rely on marks on a die, which could have resulted later when a previously used die was recommissioned, or strike to determine origin appears problematical.
The silver coins of 1922 are among the poorest struck of the Commonwealth series, and the Sydney-struck sixpences in particular are renowned for their extensive die-cracking. It is certain that the master tool responsible for the 1922 sixpences collapsed, as this mintage signals the end of the sixpence reverse with 140 edge denticles which had commenced on the 1910 Sixpence. It is possible that the Melbourne Mint in a first was responsible for adding the 143 edge denticles to the new 1923 Sixpence reverse, as the British sixpence of the same date carried 145 denticles, but the superior finish of the Australian sixpences would suggest that the London Mint supplied Melbourne with completed master tools. This reverse was used on all Australian-struck sixpences from 1923 to 1963. The London-struck 1951 PL Sixpence, with 127 denticles on the reverse, was the only coin to interrupt the run. Of course this was not the first time that the number of edge denticles was adjusted on a reverse die. The London Mint had earlier made a small adjustment to the threepence reverse, reducing the number of denticles from the 118 used on the 1910 Threepence to 115 on the 1911 Threepence. This reverse die remained in use until 1936.
The 1922/1 Overdate Threepence is a controversial coin appearing to be an early experiment by the Melbourne Mint to alter the date on a die. It is thought that in this instance the last figure on a working hub was simply hammered flat and a new figure was roughly re-entered on the ensuing die. In 1922, the Melbourne Mint did not have the figure punches needed to alter dies, so either the mint fashioned its own tool or these unrecorded coins were struck as an experiment in early 1923 when the punches were available. The 1925 Shilling is also an overdate but in this case the '3' was removed from an unutilized 1923 Shilling master hub and a '5' re-entered on the subsequent master die. This was only partly successful because the entire mintage, including the proofs, show elements of a '3' under the '5'. Although there is no record of its production, the 1933/2 Overdate Penny is similarly the product of the Melbourne Mint altering a 1932 dated hub. Why this process was undertaken in 1933 remains a mystery as penny production appeared robust with 6,781,800 coins struck. It seems likely that this overdate is the result of experimentation with just a few reverse dies, and a possible explanation is that retiring mint staff were called upon to impart their knowledge of this skill before their departure. The last of the recognised overdates is the 1934/3 Threepence which, like the 1925/3 Shilling, was derived from an unused master tool. Although no 1933 threepences were struck for circulation, a master die was prepared and the date later altered to produce the 1934/3 Overdate. It is far more common than the 1922/1 Overdate, and probably the product of more than one working die, but is still only a small part of the overall mintage for 1934. It is estimated that about 50,000 of the 3,404,000 threepences dated 1934 are overdates.
King George V died in January 1936, and Edward VIII ascended the throne. The London Mint prepared obverse tools (hubs and dies) for all denominations featuring the new monarch, but on the abdication of the king these were destroyed. No Australian coins were struck with an Edward VIII obverse. However, the hubs for the penny and threepence had already been sent to Australia and their destruction was confirmed by letter on December 19, 1936. Penny-size models of the new 1937 kangaroo reverse were made as were double-sided 1937 pattern pennies featuring the obverse portrait of King George VI. Uniface patterns of the threepence, shilling and florin are also known and some have made their way into the hands of collectors as did a double-sided 1937 Threepence of George VI. The latter coin has always been the subject of doubt as it was thought that, except for the penny, no double-sided patterns were struck, but it has recently been reported that the Royal Australian Mint holds double-sided examples of the threepence, shilling and florin in its collection as well as a master die of the 1937 Penny reverse. No 1937 halfpenny or sixpence reverse patterns are thought to exist and, coincidentally, when the first circulating coins of George VI were introduced in February, 1938 these denominations kept the old reverses.
The 1939 Halfpenny began with the long standing • COMMONWEALTH OF AUSTRALIA • reverse which commenced in 1911, but at some point during production a new design was introduced featuring a scaled down and inverted version of the kangaroo penny reverse that had been adopted in 1938. Two distinct reverse dies were used for the production of the new 1939 'Roo' Reverse Halfpenny and these reverse types, with observable differences, alternated on halfpennies produced in later years. The original London master die for the 'Roo' reverse can only have been used experimentally as very few 1939 'Roo' halfpennies of this type have surfaced. This new Type B reverse is characterised by very detailed fur lines on the paws of the kangaroo and on the underside of the tail, and a series of prominent rib lines found at the juncture of the leg and torso. However, these features may only be visible on early strikes, so the easiest way to distinguish this type is to examine the foot of the 'Y' of 'HALFPENNY' which exhibits a double foot. The Type Bm reverse is by far the more common type found on the 1939 'Roo' Halfpenny. In comparison to the Type B reverse, it is generally less detailed and is readily identified by the foot of the 'Y' of 'HALFPENNY' which is truncated on the righthand side and is best described as having a single foot. These changes were likely initiated by the Melbourne Mint which had a history of altering dies when producing a new master, and the truncated foot on the 'Y' of 'HALFPENNY' is possibly a deliberate marker to claim its additional work. As a testament to the mint's skills, it struck 100 proof halfpennies with the Type Bm reverse which were offered for sale to the public. Only a single example of 1939 'Roo' Proof Halfpenny with the rarer Type B reverse has so far surfaced.
By 1940, World War II was causing severe manpower and material shortages and the Perth Mint received a request from the Australian Treasury to help the overstretched Melbourne Mint by producing £8,000 of pennies and £4,000 of halfpennies. Penny production was immediately ramped up and the Perth Mint struck 1,113,600 pennies in 1940 marked with a surreptitious 'K.G' mint mark, distinguishing its coins from Melbourne's. But the Perth Mint did not strike its first halfpenny until 1942, the same year that the the Bombay Mint was also sub-contracted to strike Australian pennies and halfpennies. The Perth minted halfpenny was singled out by the addition of a dot after 'HALFPENNY' while the Bombay coins were identified by the 'I' mint mark on the obverse below the head of George VI, and dots before and after 'HALFPENNY' on the reverse.
It is not certain whether the Melbourne Mint supplied the Bombay Mint with dies for this emergency war issue, but if it did the reverse dies were not used directly. It is likely that a reverse model was produced by the Bombay Mint from either a struck coin or an impression taken from a reverse die of the unaltered 1939 London 'Roo' Halfpenny, and from this it derived working dies to produce the initial coinage. Consequently, the first 1942 I halfpennies retain the original denticle count and the double footed 'Y' typical of the unaltered 1939 'Roo' Halfpenny upon which it was based. Although cruder in apearance much of the original design remains, so in the Benchmark Catalogue this die is classified as a sub-Type Bb in recognition of its London origins, but also taking into account the considerable changes undertaken by the Bombay Mint. On this die the kangaroo is leaner and a re-worked eye is both raised and lidded.
The later production of the 1942 I Halfpenny and all of the 1943 I Halfpenny were struck on dies derived from the altered Melbourne Bm reverse but with further changes undertaken by the Bombay Mint. This die is characterised by a single foot on the 'Y' of 'HALFPENNY' typical of the Bm reverse but now with noticably fewer but larger denticles. Because of its further removal from the original design, a new Type C has been recognised.
Similarly, the denticle count on the 1942 I and both versions of the 1943 I pennies is fewer than the contemporary Australian-minted coins, and, like the halfpennies, the kangaroo is leaner and the eye is raised. Because of the extensive reworking of the original London design, a new Type E reverse has been recognised on the Bombay pennies. The different Type 4 obverse die used on the Bombay-struck pennies also carried far fewer edge denticles (145) than the Australian pennies (156).
The 1943 I Penny was struck with both large and small denticles and the latter has been classified as a sub-Type E(i). The denticle count on the small denticle variety remains the same, and in all other respects it appears to be the same design as the large denticle variety which had continued from the 1942 coinage. The shortening of the denticles on the later coins may well be explained by the commissioning of a new die from the model with a slightly larger central design. Effectively, this would result in the edge denticles being pushed out and shortened.
Bronze, a traditional mixture of copper, tin and zinc, was the alloy used for the halfpenny and penny denominations. Although the Coinage Act of 1909 specified that the silver coins should be sterling silver, ie 92.5% silver and 7.5% copper, there was no specified formula for bronze. There are anecdotal reports that until the early 1940s the alloy used contained up to 3% tin, but then, due to the scarcity of this metal during the war years, the alloy was adjusted to 97% copper, 2.5% zinc and 0.5% tin. This change in alloy would account for the slightly brassy look of the later mint-state halfpennies and pennies. For consistency, we have used the later composition in our coin specifications as although there is an observable difference between early and late date Australian bronze coins there is no certainty when and if this change occurred.
During World War II, the Australian government was forced to call on the San Francisco and Denver mints to strike coins to overcome a shortage of circulating currency caused by the large number of American servicemen stationed in Australia. Similarly, the coins of the Philippines were struck during WWII by the Philadelphia, Denver and San Francisco mints to allay shortages caused by the large influx of US servicemen. There is no record of master or working dies being sent from Australia to the United States and therefore the coins produced must have been the product of dies manufactured by the American mints. Similar to the emergency measures employed by the Bombay Mint, it is likely that a pantograph was used to produce coin models and eventually dies from samples of circulating Australian coins. The coins are identified by an 'S' mint mark for San Francisco and a 'D' mint mark for Denver. Mint marks have long been used by collectors to separate coins struck at different mints but the 'Benchmark Catalogue' also separates the different fonts used on those marks, ie the plain and serifed punches used by the San Francisco Mint.
The silver coins of 1946 were the first struck in quaternary silver, a yellowish-white alloy of 50% silver, 40% copper, 5% nickel and 5% zinc. Australia debased its currency partly to repay the United States for more than $12 million of silver used during the war years to strike its coins at the San Francisco and Denver Mints. In 1956, $6 million of silver retrieved from withdrawn sterling coins was sent to the United States as part payment of this debt.
Sometimes small observable changes occur within mintages of coins of a particular year. We have separated a small number of 1926 sixpences exhibiting serifying on the lettering in the reverse legend and on the '2' in the date, changes which also appear on the proofs of that year. The serif on the '2' also appeared on the earlier sixpences of the 1920s but these coins had flat based lettering in the legend, and so a sub-Type B(i) is recognised. The more common 1926 Sixpence, which we have classified as sub-Type B(ii), combines a distinctive straight bar on the base of the '2' with straight based letters in the legend.
A small change also occurs on the 1946 Florin. These coins may have a small or large ovoid in the '6' of the date. There is some conjecture that coins with a large ovoid in the '6' were the result of the stop-gap use of an inverted '9' punch on the date. The inner voids on the '6' and '9' of this variety are relatively the same size, while on coins with a small ovoid in the '6' there is a marked difference with the larger ovoid in the '9'. But as proofs of both types are known in the Museum of Victoria Collection, the alternative '6' in the date must have been deliberately employed. The difference is relatively insignificant. But as it is a long accepted variety in the Australian series, and the mintage of the two types can be traced back to the use of these two distinct master dies, a sub-Type B(i) is recognized for consistency.
The 1953 Florin started out with the large denticles on the 'Coat of Arms' reverse that began in 1938. These early 1953 florins also feature a double line that runs from the juncture of the tail of the kangaroo to the leg, which is unique to this date, and so a sub-Type B(ii) is recognised to disinguish these coins from the vast majority of 1953 florins which were struck with noticeably smaller reverse edge denticles. The new reverse continued with the 1954 'Coat of Arms' Florin, and this two-year type, classified as B(m), acknowledges a new master die made by the Melbourne Mint.
In our coin types, we have chosen to ignore small changes in the positioning of the date or the mint mark, but to include major positional shift(s) such as occur on the 1931 pennies with the 'dropped 1'. We have also separated the wide date varieties of the 1955 Perth pennies, as not only is the difference quite noticeable even to the naked eye it is also apparent that two sets of master dies were working in tandem that year. The most common coin combines an obverse Type 8 with a reverse with a closed '55' in the date. A scarcer coin has the Type 8 obverse with the wide '5 5' in the date while an extremely rare variety combines a new Type 9 obverse with a reverse with the wide '5 5'. The Type 9 obverse with the closed '55' occurs only on the 301 proofs struck for public sale and is not known as a circulating coin.
Major mistakes, such as the omission of a mint mark which occurred on a small number of 1942 I pennies are also acknowledged, and from 1951 onwards we have also recognised minute changes to the denticle count on the pennies and their orientation to the legend. This is easily determined by aligning uprights in the coin legend with the edge detail (denticles) and is a useful diagnostic tool in identifying the source of the original master die and often the mint where the coins were struck.
In late 1951, the London Mint was called upon to help strike Australian pennies and halfpennies for the first time since 1915. The Perth Mint had already released 1951-dated halfpennies without a mint mark (normally the preserve of the London Mint), and so, in a major break with tradition, the London Mint was forced to distinguish its coins by employing a new 'PL' mint mark. London in turn was unable to complete the order on time, and was obliged to sub-contract part of the order to the Heaton Mint, Birmingham which used the same 'PL' mint mark. Thus three mints were responsible for striking the 41,422,800 halfpennies dated 1951, and there are five or possibly six varieties noted. The rarest of the four Perth issues, with a reported mintage of just 126,720, used the obverse that was introduced in 1949 which is distinguished by 146 dentices and allied it with the 'no mint mark' reverse. Another variety which aligned the 'no mint mark' reverse with a new obverse with 149 denticles accounts for less than ten percent of the overall mintage and is itself a scarce coin. The 1951 Y. Halfpenny with the old obverse is scarcer than the 1951 Y. Halfpenny with the new obverse which constitutes the major production run. The 1951 PL Halfpennies struck at the London and Heaton mints used the original 'double footed' 1939 reverse that had been sent to Melbourne coupled with the old 1949 obverse. This would indicate that the new 1951 obverse with 149 dentices was an Australian production, and probably the work of the Melbourne Mint as it is thought that the Perth Mint did not have the skills to produce its own dies at this time. Interestingly, a study of the left cross bar on the 'Y' of 'HALFPENNY' on the 1951 'PL' halfpennies reveals some coins with a straight bar (60%) and some with a hook (40%) which roughly coincides with the proportions struck by the London and Heaton Mints. This may be a coincidence, but the proofs of this date have a straight bar confirming these coins were struck in London, and so it is possible the dies used by the Heaton Mint were 'marked' with a hook to single out its production.
Except for the Bombay-minted pennies of 1942 and 1943, all kangaroo reverse pennies have 81 thin and 81 thick edge denticles in which the alignment to the legend remained constant until the London-struck 1951 'PL' Penny. The London Mint produced a new master hub for this reverse from a 1937 master die, but in adding the edge detail to the ensuing master die the alignment to the legend was altered. Although the number of denticles remained the same on this reverse, we have classified it as a new Type F because from this die the Melbourne and Perth branch mints diverged from the lead offered by the London Mint in positioning the legend on their later master dies. Both the Melbourne and Perth mints added the edge denticles with slightly different orientations, effectively creating a number of sub-types which help identify where the coins were struck.
By 1952, the Perth Mint had acquired the skill to produce its own master and working dies. The mint received two distinct 1951 penny reverse master tools directly from London. These formed the basis of its 1952 master dies. As an interim measure, Perth received a 1951 Type D reverse master die with edge detail which proved the source of the early 1952 die varieties which are known by the different versions of the '2' in the date. It also received a hub of the new Type F reverse and produced a master die to which denticles were added. The working dies that resulted produced the bulk of the 1952 pennies struck by the mint. The Perth Mint used the same reverse master die on its 1953 and 1955 pennies before altering the edge alignment on a new master used from 1956. Although it continued to use the Type D reverse on its pennies struck in 1952 and 1953, the Melbourne Mint did experiment with the new Type F reverse in 1953 producing a small number of pennies 'sans serif', ie missing its traditional serif on the first '5' of the date. The Melbourne Mint adopted this new type from 1955, which is apparent from the abandoning of the serif on the '5's in the date.
The timeline of Australia's pre-decimal coins from 1910 to 1964 provides a valuable insight into its history, and a number of pivotal events were depicted on its designs. In 1927, the opening of Australia's first Parliament House was commemorated on a florin, as was the centenary of the founding of Melbourne on the 1934-5 Florin. In 1937, a crown was struck for the coronation of George VI but the purpose of that coin was defeated by the release of a 1938 coin of the same design. The Golden Jubilee of Australia's Federation was also celebrated by a special florin in 1951, and in 1954, the Royal Visit Florin marked the first time a reigning monarch had toured Australia. The last pre-decimal coins were struck in 1964 before Australia transitioned to decimal currency on February 14, 1966, thus bringing to an end the 'imperial' currency inherited from Great Britain. Perhaps as a salute to the past, the Royal Mint in London helped strike the first decimal coins, and the Royal Australian Mint in Canberra, which had replaced Melbourne as the senior issuing authority, called on the Melbourne and Perth mints to help strike the new one and two cent coins.
The 'Benchmark Catalogue' of Australian pre-decimal coins contains all the intentional mint-generated varieties identified to date. Other varieties which are the result of worn dies such as die cracks, design loss or field flaws are not included in the catalogue. In determining the classifications, such as the obverse and reverse types used for the 'Benchmark Catalogue', we have attempted to set a standard protocol that is applied to all denominations. For example, various publications refer to the 'English', 'London', and 'Indian' obverses used on Australian pennies of George V, but in fact the first two descriptors ie 'English' and 'London' are the same. To overcome this problem we have reserved the term 'English' for obverse master tools (hubs or dies) used or supplied by the London Mint. The term 'London' is similarly reserved for the reverse master tools (hubs or dies) used or supplied by the London Mint.
The mintage figures of various coins largely reflect those published in 'Australian Coinage - An Account of Particular Coins (1991)' by W.J.Mullett, who, as a senior officer at the Melbourne Branch of the Royal Mint, was the person responsible for recording coin production figures. This has resulted in the reappraisal of the rarity of certain coins such as the 1942 'Melbourne' Threepence, the mintage of which has been dramatically reduced from the previously thought 528,000 to 380,000. Similarly the mintage of the 1928 Shilling has been halved to 332,000 explaining why so few of these coins have been found in high grade. For some years also we have broken up mintages to accomodate a number of varieties usually the product of experimental dies, but as no official figures exist, these can only be the best estimates of the author based on over 30 years of industry experience.