Mount Isa, a mining town and the biggest population centre in north-west Queensland, is 820 km west of Townsville, 160 km from the Northern Territory border and 350 km south of the Gulf of Carpentaria. It is situated in an extensive mineral-rich region stretching from south of Cloncurry to west of Burketown. Unlike many other great mining towns, including Broken Hill and Charters Towers, Mount Isa is unlikely to run out of minerals to mine, having mastered the treatment of large volumes of lower grade ore.

The Mount Isa mining field was discovered by an itinerant prospector, John Campbell Miles (c1883-1963) in 1923. Miles was camped on the Leichhardt River and took rock samples from an outcrop, knowing by their weight that they were mineralised. A government assayer at Cloncurry found an astonishing lead content of up to 78%. A few months later the Government geologist confirmed the mineral potential, starting a rush of leasehold applications. Miles named the outcrop Mount Isa, explaining in the 1950s that he did so in memory of the Mount Ida mine, about 20 km north-west of Kalgoorlie, Western Australia. Miles never explained why he substituted Isa for Ida.

A rudimentary mining township soon formed and Mount Isa Mines Ltd was floated in January 1924. Storekeepers brought buildings from other towns, mainly Kuridala, south of Cloncurry, and two open-air picture theatres were started. By the end of 1924 there were a provisional school, a progress association and a surveyed town on the east side of the Leichhardt River. Many businesses had set up next to the mine on the west side of the river. Putting the town on the east side indicated a certain sensitivity to good town planning.

COMPANY TOWN

A Cloncurry businessman, Douglas McGillivray, began to take out options to purchase individual mining leases which by 1925 enabled Mount Isa Mines to acquire most of the critical sites. Further accumulations followed, giving MIM 370 ha in 1929 and 1176 ha in 1932. Large-scale finance was needed, involving investment by the Russo-Asiatic Corporation in 1927. The acquisition of leases cost £245,000 and the cost of development to 1932 was about £4 million. The time scale was: 1923-25 consolidation of leases; 1924-26 underground exploration; 1927-30 ore reserve drilling and metallurgical tests; 1928-33 plant construction and modification. There was a ten year lead time between discovery and production.

In May 1929 the railway was extended from the old mining town of Duchess to Mount Isa, causing a five-fold population increase to about 3000 by Christmas. The Catholic church building was transported from Duchess in 1929. MIM built a town dam on Rifle Creek, started building well-designed miners' houses, laid out sports facilities and roads and planned a tree-lined park. The locating of the railway station on the east side of the river persuaded many west side businesses to move to the new town, but within a year it was found that the company town was a better appointed settlement than the official east side town under the management of Cloncurry Shire. MIM's hospital, sensibly located near the site of potential mining accidents, caused considerable discontent when compared with the less well-appointed cottage hospital in town. The emerging divide between town and mine settlements was physically manifested when the Leichhardt River occasionally flooded.

MIM's generous civic investment was ended by depressed metals prices in the 1930s; profits repaid interest on loans but were insufficient for a dividend until 1947. After the Depression, the company resumed large civic contributions, owing chiefly to the influence of its general manager, the American Julius Kruttschnitt, who was chairman from 1937 to 1957. Kruttschnitt proved to be community minded, involving himself in its social and sporting activities. His wife was active in the CWA and the Australian Inland Mission.

Despite the call on metals for munitions during World War II, MIM did not do well out of the war. Silver-lead treatment ceased and the mine concentrated on copper production. Labour shortages were critical. Mount Isa was a potential enemy target, scarcely an encouragement for workers to stay, and manpower controls were weakly enforced. Thousands of American soldiers were stationed at Mount Isa, camped at Soldiers Hill (later a suburb south-west of the town centre). It was only the postwar tripling of lead prices that enabled MIM to pay its first ever dividend in 1947.

The rise in lead prices enabled a lead bonus to be included in miners' wages. This was not a site allowance but a profit-sharing payment. MIM boomed during the Korean War period and wages more than doubled. Employees working in the copper smelter also received a bonus. During the 1950s the population doubled. Beer consumption and gambling at Mount Isa boomed. MIM, in the grand, some would argue paternalistic, tradition of a company town, created an Olympic swimming pool (1948), sealed roads, employees' clubs and the Marie Kruttschnitt Ladies' Club. Ordinary retail and business amenities were over-stretched by the expanding population, giving rise to criticisms of both the MIM town and the east side town under Cloncurry Shire. Housing shortages existed in both towns.

'OASIS OF THE OUTBACK'

Population growth and the resulting housing shortage led to MIM housing and cooperative housing schemes in new suburbs such as Leichhardt and Soldiers Hill. Another dam, Lake Moondarra, was constructed. A drive-in cinema, 'Tropicaire', was opened in 1956, and sophisticated recreation came when beach sand was transported to the lake in 1960. From here families could watch youngsters paddling or adults water skiing. By 1959 the east side town had matured with a range of chain stores and services; MIM closed its Community Store. The opening of an 80-bed Base Hospital in 1960 was followed by the Flying Doctor Service transferring its headquarters from Cloncurry to Mount Isa in 1964.

The town's prosperity came to a halt when a dispute over wages and a split among workers between the AWU and an American union agitator, Pat Mackie, resulted in a mine stoppage during most of 1964. In a long and bitter dispute the Country and Liberal party state government used the police to restrict the movement of the pro-Mackie unionists. When the dispute ended many employees had left town, and mine operations resumed slowly.

Mount Isa absorbed Barkly Tableland Shire in 1963 and was raised to city status in 1968. The Sunset and Pioneer housing areas were laid out between 1967 and 1971. Just as chain stores had established outlets in the 1950s, discount department stores and drive-in centres were opened in the 1970s. With the help of MIM the city opened a Civic Centre in 1974. Water supply was secured in the 1970s when the Lake Julius dam was built on the Leichhardt River, 100 km north of Mount Isa. From the mid-1950s to the mid-1970s Mount Isa's population went from 8000 to 25,000; in the next 25 years the figure slipped back to 21,000.

Many remote mining towns decline or fade completely within 70 years of their discovery. Mount Isa, however, developed the means of profitably treating large-volume, lower grade ore bodies, carefully managing labour costs. MIM diversified into coal and installed a copper smelter at Townsville, a partial solution to labour disputes stopping production in a single centre and avoiding over-reliance on changeable world copper prices. MIM Holdings reported a long-term cost reduction strategy at Mount Isa, including improved management and workplace reforms successfully negotiated with the unions. MIM Holdings was acquired by Xstrata in 2003.

In 1976, 40.7% of Mount Isa's workforce was in mining. In 2011 employment in mining engaged 28% of the workforce. Apart from primary schools, it has two State high schools, a Catholic high school, the Christian secondary college and a large TAFE campus. Its tourist attractions include the mine complex, the Museum of North West Queensland, the outback, Riversleigh fossil centre, an annual rodeo, and a festival of the arts. The careful harvesting of water and treatment of waste mine water contributes to Mount Isa's image as an 'Oasis of the Outback'.

Mount Isa's census populations have been:

Census DatePopulation
19333241
19547433
196113,358
197125,497
199123,667
200120,525
200618,857
201120,570

At the 2011 census 14.9% of residents were Aboriginal and Torres Strait Islander people.

Further Reading: 

Don Berkman, Making the Mount Isa Mine 1923-1933, Carlton, Vic, the Australasian Institute of Mining and Metallurgy, 1996

Geoffrey Blainey, Mines in the spinifex, Sydney, Angus & Robertson, 1960, 1970

John Elliott, Mount Isa portrait, Brisbane, Boolarong Publications, 1988

Noreen Kirkman, Mount Isa: oasis of the outback, Townsville, School of History and Politics, James Cook University, 1998

Mount Isa Shire and City and Mount Isa Suburbs entries