There are some surprising patterns that can be revealed in Australian coins if you take a closer look.
If you look at Australian silver coins, heavier coins weigh more. For five cent, ten cent and twenty cent coins, the weight of the coin is proportional to the value. This means that five dollars weighs the same, whether it’s made up of five cent, ten cent and twenty cent coins, or a mixture of the three. However, fifty cent coins don’t match the pattern – they are only a few grams heavier than twenty cent coins.
When you put different coins into the jar, you might find they come up to different heights. These jumbled piles of coins all have different volumes. However, the coins themselves are all made of the same metal, and they each weigh the same amount. If you melted the coins down, each pile would have the same volume of metal. The difference comes from how the coins are arranged in the jar, and how big the gaps between the coins are.
Coins have been around for thousands of years. In many cultures, coins have been made of precious metals such as silver or gold. The value of the coin came from the metal in the coin, so a heavier coin would be worth more. These days, most coins are made of relatively cheap metals, and heavier coins are not always more valuable.
When Australia changed to dollars and cents in 1966, fifty cent coins were round and made of a different metal to five, ten and twenty cent coins. It was uneconomical to continue to make these coins – there was a lot of silver in them and the price of silver increased. When the mint reissued 50 cent coins, they chose a different shape – a dodecagon – to help prevent confusion with 20 cent pieces. This might explain why five dollars worth of fifty cent coins is relatively light.
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14 November, 2021 at 9:31 am
When i put 772 5c aus coins on my scale at work, what is it worth in dollars and cents. Give me the number to convert weights of denominations to dollars please. It would be useful to many people
14 November, 2021 at 11:24 pm
should be about 2185 grams!
from the Australian Mint website, one 5c coin weighs 2.83g, so multiply by 772 for your answer!
One dollar is 20 x 5c, and weighs about 57g
one kilogram is about 353 5c coins, for a value of $17.65
17 February, 2023 at 3:31 pm
I really miss the old 1 and 2c coins. I was 10 when they got rid of them and it upset me.
17 February, 2023 at 3:34 pm
I wish I had good news on that front. Unfortunately, we might lose the 5 and 10 cent coins soon:
https://www.abc.net.au/news/2020-01-30/5-and-10c-soon-to-die-graceful-death/11910736