1943 saw the replacement of paper money used in internment and prisoner of war camps with metal tokens. Read a little of this history:
[1943 ‘Canteen Tokens For Internees’, News (Adelaide, SA : 1923 – 1954), 3 February, p. 6. , viewed 03 Oct 2019, http://nla.gov.au/nla.news-article128330429%5D
In February 1943, the Minister for the Army announced the introduction of metal tokens for use in internment and prisoner of war camps.
Memorandum 3rd March 1943, National Security Regulations, Prisoners of War and Internees – Canteen Tokens recorded: ‘ It is intended that metal tokens shall be used for all prisoners of war and internment camps instead of paper chits.’
Interestingly, New Zealand utilised Australian minted money tokens; a five shilling coin is held in Museum of New Zealand Te Papa Tongarewa in Wellington.
History of Paper Bank Notes, Paper Chits and Canteen Coupons
Internees in Hay Camp 7 produced their own currency, an example can be seen at the Sydney Jewish Museum. Today, at auction one note can fetch up to $12,500.
Hay Camp Currency with Faith details the currency used and also examples of the paper chits which were used.