Osmiridium

The rugged country around the Pieman River where osmiridium was mined – mostly far from any bridge or road
(AOT, NS241/1/33)

Osmiridium is a popular name for a naturally occurring alloy of the metals iridium and osmium. Corrosion-resistant, it is used in the manufacture of a variety of articles from pen nibs to munitions. First recognised in the 1880s as an undesirable impurity associated with alluvial gold in western Tasmania, it was discarded by the miners. A penalty was imposed by the Mint for its removal from gold.

In 1909 a dramatic increase in price created a boom for the metal, with a rush of miners moving into a number of western mining fields. The collapse of the Russian industry as a result of war and revolution saw prices continue to rise. By 1920 the price reached £38 per ounce and that year the Pieman fields produced 2009 ounces with a value of £77,104. Tasmania had now become the world's largest producer. A second osmiridium rush followed in 1925 with the commencement of alluvial mining at Adamsfield in the state's south-west. In that year £105,570 was paid to miners, but by 1930 the boom had passed with only £16,235 paid to all the miners in the state.

The excitement and adventure of the Tasmanian osmiridium-mining boom was the subject of a novel, Jewelled Nights, by Marie Bjelke Petersen, published in 1923. In 1925 a film based on the book starring Louise Lovely was made, largely in the Pieman district. Production of osmiridium continued until 1954, by which time more than 881 kg had been mined.

Further reading: A Alexander, A mortal flame, Hobart, 1994; C Burrett & E Martin (eds), Geology and mineral resources of Tasmania, [Brisbane], 1989; A McIntosh Reid, Osmiridium in Tasmania, [Hobart], 1921; C Bacon, 'Notes on the history of mining and exploration at Adamsfield', Mineral Resources Tasmania Report 1992/30, 1992.