If you refer to the packaged "Centenary of Federation medallion" given to school children, probably not much since there were over 2 million issued. They are a "Collectible" and value will incease over time. If you refer to the "Centenary of Federation medallion" included as part of the 2001 Proof set of coins, it will be worth nothing without the rest of the set.
$2,999
A Centenary of Newcastle (1797-1897) silver medal/medallion, depending on condition, could fetch anything from $10 to $50 AUD. A reputable coin dealer will be able to give a more accurate valuation.
3,829 of these sets were released - they sell via online auction for anywhere between $50 and their catalogue value of $95.
Your coin is an Adelaide (South Australia) Jubilee medallion in the same year as Queen Victoria. In mint condition, your medallion might fetch up to $10 AUD. A reputable coin dealer will be able to give a more accurate valuation.
As of September 2012, the limited edition Wayne Gretzky retirement medallion has a value of $200usd.
Please check your coin. The Centenary of Melbourne was in 1935. The Australian 1934/35 sterling silver Florin commemorating the Centenary was sold to the public in 1934 and 1935.
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$20.00
Western Australia does not mint its own coins. Please give more information.
An Australian 2008 sterling silver Five Dollar coin (Scouts Australia Centenary)(Proof), uncirculated and in absolute mint condition could fetch up to $95 AUD. There were 5,000 minted. A reputable coin dealer will be able to give a more accurate valuation.
Oh, isn't that just a happy little question! The value of a NAHC collectors medallion can vary depending on factors like its condition, rarity, and current demand. Remember, the true value of a collectible is the joy it brings to you when you admire it!