Mineral wealth had been suspected here since the explorer James Venture Mulligan passed through in 1874, and the magnate John Moffat had been erecting small exploratory smelters in the district since the 1890s. But Chillagoe's real transformation came with the railway. By June 1901 the line was complete; by September the heavy, modern smelting machinery it carried in was running. Suddenly the surrounding mines - at Mungana, Zillmanton and Redcap - could work at industrial scale, feeding ore to furnaces equipped with the most up-to-date plant of the era. Over its working life the smelter would treat some 1,250,000 tons of ore and yield around 60,000 tons of copper and 50,000 tons of lead, along with some 6.5 million ounces of silver and 175,000 ounces of gold.

The story that follows reads like a long argument between ambition and arithmetic. Fire destroyed a large part of the works in 1912; flues collapsed; water jackets burst; coke ran out and shut the furnaces down. The plant was rebuilt, modified and restarted again and again. In 1914 the company simply gave up and closed the smelters, and they sat idle through the World War I metals boom - the cruel irony being that rival smelting districts enjoyed their greatest prosperity while Chillagoe stood cold. When the Queensland Government took over the operation after 1918, it kept the furnaces lit not for profit but as policy: a deliberate act of welfare, manufacturing work in a depressed mining region. By the late 1930s the plant was running at a quarter of its capacity, railing more than half its ore nearly a thousand miles from the Cloncurry field, losing money every year.

The smelter's strangest legacy is political. When the State bought the Mungana mines in 1922, the price was grossly inflated - and a later inquiry would find that two of the most powerful men in Queensland had been secretly profiting. 'Red' Ted Theodore, premier from 1919 to 1925 and by 1929 the Federal Treasurer of Australia, and his successor William McCormack, premier from 1925 to 1929, had each quietly held a quarter-share in the properties sold to the government they led. A Royal Commission opened into what became known as the Mungana Affair, and the litigation that followed in 1931 destroyed both men's careers. The smelters had outlasted their usefulness as industry but proved devastatingly effective as a weapon in Queensland politics.

War finally ended it. In 1942, with metal prices surging, a wartime review of Australian production judged the rundown old smelter unfit to continue, and in July 1943 the furnaces went out for the last time. The buildings were auctioned, the machinery dispersed, the bricks sold off to private buyers. But the bones remain, and they are remarkable. Three tall brick chimneys still rise over the site and the township - one round, one octagonal, one scarred where lightning has struck it - unique as a surviving group in Queensland. Steel furnace mounts, copper converter vessels and the largest slag dump in the state spread out toward Chillagoe Creek, where a single smelter family's house still stands. Only a handful of Queensland mining sites compare, and Chillagoe alone preserves the evidence of the smelting itself.