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A Decimal Restoration

As inflation increased in the 1970s and 1980s, new coins and higher-denomination banknotes were introduced. The condition of the $1 and $2 banknotes deteriorated quickly owing to their rapid circulation to make transactions, and so their replacement by coins – a $1 coin in 1984 and a $2 coin in 1988 – reduced the costs of maintaining the currency. The printing of the $50 banknote in 1973 and $100 banknote in 1984 were the first occasions that higher-denomination banknotes had been issued since the First Series (1913–1914).

Designed by Gordon Andrews, the $50 banknote's theme of scientific innovation reflected Australia's increased public investment in research. The design focussed on Howard Florey, the Adelaide-born pathologist who progressed penicillin as an antibiotic drug, and Ian Clunies Ross, a leading figure of the Commonwealth Scientific and Industrial Research Organisation (CSIRO). The intricate backgrounds of the banknotes include scientific miscellanies of Penicillin notatum, white blood cells and colonies of bacteria accompanying Howard Florey, while the portrait of Ian Clunies Ross is supplemented by images of a microscope and telescope, chromosomes and snow crystals, cellular structure in plants and transistors in computer circuitry.

Reproduction of snow crystal structure adapted for the $50 banknote, 1973.

Reserve Bank of Australia Archives, NP-002077.

Image of transistors in computer circuitry, used on the $50 banknote.

Reserve Bank of Australia Archives, NP-002075.

The $100 banknote was designed by Andrews' colleague, Harry Williamson, who extended the scientific theme and introduced his own style of distilled clarity. Underpinned by the idea of discovery, the banknote portrayed the astronomer John Tebbutt and Douglas Mawson, whose scientific contributions included three Antarctic expeditions. The design portrays Mawson in Antarctica against a background of geological strata formations that he studied in the Flinders Ranges of South Australia. John Tebbutt is pictured beside his observatories at Windsor, New South Wales, where he helped to lay the foundations for Australia's involvement in astronomy with the discovery of major comets.

The $100 banknote was the first new banknote printed at the Reserve Bank's printing works at Craigieburn, Victoria. Opened in 1981, the facility anticipated the industry's growth and evolving technical requirements. As mentioned previously, the counterfeit of the $10 banknote in 1966 had prompted the Reserve Bank to investigate technology that might prevent future counterfeiting. The Bank began a process of scientific collaboration with the CSIRO and some two decades later, its progress was evident in an Australian invention – polymer banknotes, the subject of the next guide in this series.

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