This coin was issued in Australia.
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Light Horse WW1 2017 Stamp and Coin Cover | The Perth Mint
The Mint says about this coin:
Light Horse
The Perth Mint and Australia Post are pleased to present this stamp and coin cover commemorating the legendary Australian Light Horse who served during the First World War. $1 Aluminium Bronze Coin This $1 coin is struck by The Perth Mint from aluminium bronze. Australian Legal Tender Issued as legal tender under the Australian Currency Act 1965, the Ian Rank-Broadley effigy of Her Majesty Queen Elizabeth II, the 2017 year-date, and the monetary denomination are shown on the coin’s obverse. Historic WWI Design The coin’s reverse depicts a member of the Australian Light Horse charging on his horse. The design includes the inscription AUSTRALIAN LIGHT HORSE WWI, as well as The Perth Mint’s traditional ‘P’ mintmark. Presentation Packaging OFFICIAL AUSTRALIA POST STAMP Affixed to the envelope is an official Australia Post $1.00 stamp. The stamp is postmarked for the first day of issue and the envelope includes Australia Post’s Seal of Authenticity. Each coin is presented in a presentation card featuring photographic images from WWI.
Monetary Denomination (AUD): 1
Metal: Aluminium Bronze
Nominal Gross Weight (g): 13.50
Maximum Diameter (mm): 30.60
Maximum Thickness (mm): 3.10
Maximum Mintage: Unlimited
Perth Mint Item ID: 17B60AAA
Issue price: AU$ 17.95, US$ 12.86 | 
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