On the 145h of February in 1966, decimal coins were first introduced along with dollar notes to replace the British currencies that were being used up until this point in Australia. Coins have an obverse and reverse side, more commonly known as heads and tails, which feature different designs. 

All Australian decimal coins currently feature an image of Her Majesty Queen Elizabeth II on the obverse side as well as the year the coin was minted. Originally, the reverse sides of Australian coins featured our native fauna and designs including these unique animals can still be seen today. However, some of the newer coins instead commemorate important figures or events in Australian history with their design.

Australian 5 cent coin

The five cent coin

The 5c coin’s reverse side depicts an image of an echidna, designed by Stuart Devlin. The image of the 5c coin has not changed since it was introduced in 1966. The 5c coin consists of 75% copper and 25% nickel, being circular in shape with a milled edge.

How much does the five cent coin weigh? The five cent coin weighs 2.83 grams with a diameter of 19.41 millimeters. 

Australian 10 cent coin

The ten cent coin

The 10c coin’s reverse side depicts an image of a lyrebird, designed by Stuart Devlin. The image of the 10c coin has not changed since it was introduced in 1966. The 10c coin consists of 75% copper and 25% nickel, being circular in shape with a milled edge.

How much does the ten cent coin weigh? The ten cent coin weighs 5.65 grams with a diameter of 23.60 millimeters. 

Australian 20 cent coin

The twenty cent coin

The 20c coin’s reverse side depicts an image of a platypus, designed by Stuart Devlin. This image of the 20c coin has been used since it was introduced in 1966, along with newer commemorative designs. The 20c coin consists of 75% copper and 25% nickel, being circular in shape with a milled edge.

How much does the 20 cent coin weigh? The 20 cent coin weighs 11.30 grams with a diameter of 28.65 millimeters. 

Australian 50 cent coin

The fifty cent coin

The 50c coin’s reverse side depicts the Australian Coat of Arms, designed by Stuart Devlin. This image of the 50c coin has been used since it was introduced in 1966, along with many commemorative designs. The 50c coin is the only decimal coin to be changed since it was introduced in 1966. 

The original 50c coin consisted of 80% silver and 20% copper, being circular in shape with a milled edge. It weighed 13.28 grams with a diameter of 31.65 millimeters. The main reason that the original 50c coin stopped being produced was the swift increase to silver prices, making the coin too expensive to manufacture. People also complained about the confusion the coin created due to it being very similar in size to the 20c coin.

The current 50c consists of 75% copper and 25% nickel, being decagonal (12 sided) in shape with a plain edge.

How much does the fifty cent coin weigh? The fifty cent coin weighs 15.55 grams with a diameter of 31.65 millimeters. This version of the 50c coin was released in 1969, with a different shape and made from a different alloy compared to the original 50c coin.

Australian 1 dollar coin

The one dollar coin

The $1 coin’s reverse side depicts an image of five kangaroos, designed by Stuart Devlin. This image of the $1 coin has been used since it was introduced in 1984, along with a number of commemorative designs that have been released since.

The $1 coin consists of 92% copper, 6% aluminium and 2% nickel, being circular in shape with a milled edge.

How much does the one dollar coin weigh? The one dollar coin weighs 9 grams with a diameter of 25 millimeters. 

In the mid-1970s, planning began to introduce a $1 coin that could be used in coin-operated machines. This new coin would replace the paper $1 note, which due to frequent usage would wear down very quickly.

Australian 2 dollar coin

The two dollar coin

The $2 coin’s reverse side depicts an image of an Australian Aboriginal elder, the Southern Cross and Australian flora. This image of the $2 coin was designed by Horst Hahne, who drew inspiration from a drawing by Ainslie Roberts. This image has also been used since it was introduced in 1988, along with a number of commemorative designs that have been released since.

The $2 coin consists of 92% copper, 6% aluminium and 2% nickel, being circular in shape with an interrupted milled edge.

How much does the $2 coin weigh? The $2 coin weighs 6.6 grams with a diameter of 20.50 millimeters.

Similarly to the $1 coin, the $2 coin was introduced to replace a paper note that wore down due to frequent usage. Much consideration was given when deciding on the size of $2 coin, including the following:

  • The needs of visually impaired citizens in the community
  • The security of the coin, ensuring it cannot be replicated easily
  • The need to avoid shaped coins
  • Deciding on the best size and thickness of the coin
  • Allowed for the possibility of introducing new coins in the future

The one and two cent coins

The 1c coin’s reverse side depicted an image of a feather tailed glider, with the 2c coin’s reverse side depicting an image of a frilled-neck lizard. Both of these images were designed by Stuart Devlin, and were the only images used since the coins were introduced in 1966.

Both coins consisted of 97% copper, 2.5% zinc and 0.5% tin, being circular in shape with a plain edge.

How much does the one and two cent coins weigh? The 1c coin weighed 2.60 grams with a diameter of roughly 17.65mm, while the 2c coin weighed 5.20 grams with a diameter of 21.59mm.

On the 21st of August in 1990, it was announced that these coins would stop being produced. The main reasons for the removal of these coins was inflation lowering their value, as well as the high cost of bronze. Despite being removed from circulation starting in 1992, they are still classified as legal tender even to this day.