This is a gold proof version of the mint set of Australian circulation coins issued in 2025. Unlike the sets in base metals, it contains the definitive "Coat of Arms" 50 cents coin and not a commemorative.
The Mint says about the set:
"Each coin in this 2025 Fine Gold Proof Year Set is struck to the Mint’s high-quality proof standard - perfectly highlighting the effigy of His Majesty King Charles III in a stunning frosted finish, providing a stark contrast to the mirror-finished field.
Since 1965, the Royal Australian Mint has been releasing annual year sets, providing collectors with a complete set of coins from each year. The Mint continues this tradition with the 2025 Six-Coin Fine Silver and Gold Proof Year Sets, which mark the culmination of a monumental effort that began in 2022 when His Majesty King Charles III ascended the throne. These coin sets celebrate the significant transition to the new Monarch’s effigy, a defining moment reflecting Australia’s enduring connection to the Crown.
The set features the effigy of His Majesty King Charles III, created by Welsh engraver Daniel Thorne."
Note that, owing to the delay in the adoption of the King's portrait on Australian coinage, no regular gold set was issued in the previous year (2024).
The set comes in a timber presentation case with the coins individually encapsulated in plastic, and with a numbered Certificate of Authenticity. | 
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