As noted in our comments, the 1920 Type 7 Square Penny has been on an impressive growth path over the past few years.
The reason is a combination of the coin’s extreme scarcity and its popularity.
So, let's look at its scarcity.
We estimate that twelve 1920 Type 7 Square Pennies are available to collectors. (Compare that figure to the number of 1930 Pennies around.)
Twelve is a minuscule number, particularly when you consider that the twelve coins are never going to be slapped onto a table in one hit and offered for sale at the one time.
So how often can a buyer realistically expect to see a 1920 Type 7 on the market?
Our research confirms that you might expect to be offered a Type 7 Square Penny once every two to three years. Now that's rare!
Now let's look at the coin’s popularity.
The Kookaburra Square Penny captures a great moment in time in Australia's history and is viewed as a ‘classic Australian coin rarity'.
That's a title that is used sparingly, but glowingly, reserved for pieces such as our first silver coins, the Holey Dollar and Dump. Our first gold coins, the Adelaide Pounds.
And our first cupro-nickel square coins, the Kookaburras.
Even the Royal Australian Mint, Canberra, has recognised the historical importance of Australia's Kookaburra coinage.
The mint's latest decimal coin release, comprised of three coins, commemorates the Kookaburra Pattern coins.
Each coin has a 25 cent denomination and is square shaped, depicting a design used on the Square Pennies struck in 1919, 1920 and 1921. (The years in which the Square Pennies were struck.)
It is noted that we have already taken several enquiries from mint customers keen to acquire an original Square Penny.
Now for a bit of history ...
The rumblings of a Republican movement were heard in 1919 when the Australian Labor Government decided to discard the traditional British penny and halfpenny designs and replace the coins with square coinage featuring the kookaburra.
The change to incorporate Australia's native bird onto our coinage was politically motivated.
A wave of nationalism was sweeping the country post World War I and the Government saw political advantage in tapping into the mood of the people by introducing a uniquely Australian flavour to our coinage.
A kookaburra design and the depiction of the monarch without a crown were two of the elements of the new coinage that while highly contentious and provocative, the Government believed would be accepted. A new metal was also used. The square kookaburra coins were tested in cupro-nickel.
Trials commenced at the Melbourne Mint in 1919 and continued until 1921 with the test pieces ultimately passed to dignitaries and Government officials to assess their reaction.
It is believed that over the three year period 200 pieces, of various designs, were produced.
The response to Australia’s square coinage was however poor. There was widespread public resistance to change, while the elderly rejected the small size of the coins.
However, the final decision not to proceed seems to have been based mainly on another consideration. The large number of vending machines then in operation requiring a circular coin.
The impetus for change was further eroded when William Watt, the most influential advocate of the nickel kookaburras, suddenly resigned his position as Treasurer before the necessary regulations were in place.
The kookaburra coins never went into production and Australia lost a great opportunity to go its own way.
But with only the 200 prototypes to show as evidence of the Government’s grand scheme, Australian coinage gained another wonderful collector piece. And a prized coin rarity.