1920 Kookaburra Square Penny design type 9, also known as the 'Square Legend Kooka'

For the buyer contemplating a Square Penny purchase, two considerations should be foremost.

The first is the quality. The Square Pennies were test pieces and were not struck under the heady controls of a proof striking. It is also noted that the coins were passed to the public for opinions, introducing the possibility of mishandling.

Our comments are as follows. This coin is visually very attractive with superb proof-like reflective surfaces and a highly detailed design. We also note uniform edges on both obverse and reverse, acting as the perfect frame for the design.

The second consideration is the design type. The style of the kookaburra and the style of lettering is critical to assessing the rarity of the coin for while all Square Pennies are rare, some designs are far rarer than others.

Our comments are as follows. We estimate that only seven 1920 Type 9 Kookaburra Pennies are available to collectors. That minuscule number translates to infrequent appearances on the market of perhaps once every six to seven years. We note that a type 9 Kookaburra Penny was last offered at auction in 2016.

The year '1920' is indeed a glamorous one for the industry for it hosts some of the rarest and most famous coins of the Australian numismatic industry.

It's a stunning line-up that includes:

• Australia's rarest florin, the 1920 Star Florin.

• One of Australia's most valuable shillings, the 1920 Star Shilling.

• Australia's most valuable sovereign, the 1920 Sydney Mint Sovereign.

• The 1920 Kookaburra Square Halfpenny, the rarest halfpenny of the series and a coin that is recognised as one of the "great Commonwealth coin rarities".

And last, but no means least, this coin. The 1920 Type 9 Kookaburra Square Penny.

That currency reflects the mood of a nation – and the agenda of a Government - is never more evident than with the Square Penny and Halfpenny series and its mooted introduction in 1919.

The proposed change was pure politics. With some saying it was the rumblings of a republican movement way ahead of its time, the Labor Government wanting to break away from the traditional British designs of Australia’s then copper penny and halfpenny.

A wave of nationalism was sweeping the country post World War I and the Government saw advantage in tapping into the mood of the nation and introducing a uniquely Australian style into our currency by depicting a laughing kookaburra on our coinage.

Tests 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.

The extreme scarcity of choice quality Square Pennies is connected to the fact that the coins were test pieces and were not struck to the exacting standards of proof coining.

Given to dignitaries to assess their reaction, there was no packaging and we know that not every dignitary was a collector and would have handled them with care.

Some of the coins must have been tucked into a fob pocket for they have circulated. Others could have rattled around a top desk drawer. Or passed around to colleagues … introducing multi possibilities of mishandling.

Public reaction to the introduction of the square coinage was 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 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 coin rarity.