In 1926 Hampden Cloncurry conceded defeat and offered its assets for sale by tender, most being acquired by Mount Elliott, who finally gained control of virtually the entire Cloncurry copper field and belatedly fulfilled William Henry Corbould's vision of 1909 for amalgamation.

[1][3] In 1926 the company started building the first 1,000 long tons (1,000 t) per year unit of a large electro-chemical copper treatment plant at Cloncurry on the outskirts of the town adjacent to the Great Northern railway line.

This comprised crushing, roasting furnace, leaching vats and a cell house section and was completed in April 1927.

On the second level there were 24 wooded tanks 3.7 metres (12 ft) long, lined with lead, and containing electrolytic cells, cathodes, and anode bars.

A spray cooling plant consisting of a concrete reservoir 18 by 18 metres (59 by 59 ft) and 1.5 metres (4 ft 11 in) deep with a series of spray pipes and nozzles operated from an electric centrifugal pump, was designed to cool 30,000 imperial gallons (140,000 L; 36,000 US gal) of water an hour.

[1][2] It has been asserted that the company had infringed a foreign patent, but cost factors may have influenced the decision to close the plant.

These structures include a flue and iron chimney base and a vertical boiler alongside a concrete tank.

[1] The fifth component of the site is the foundations of a former laboratory building, constructed with mud brick walls with cement render on exterior and interior surfaces.

[1] Mount Elliott Company Metallurgical Plant and Mill was listed on the Queensland Heritage Register on 17 June 2003 having satisfied the following criteria.

Its construction testifies to the optimism held by the company for a centralised modern plant to service all their scattered ore reserves across the region.