Mount Elliott Company Metallurgical Plant and Mill

General

Classification

State Heritage

Register status

Entered

Date entered

17 June 2003

Type

Mining and mineral processing: Plant—metallurgical/electrolytic

Theme

2.2 Exploiting, utilising and transforming the land: Exploiting natural resources

Construction period

1926–1927, Mount Elliott Company Metallurgical Plant and Mill (1926 - 1927 April)

Historical period

1919–1930s Interwar period

Location

Address

Via Sheaffe Street, Cloncurry

LGA

Cloncurry Shire Council

Coordinates

-20.72005384, 140.49974156

Significance

Criterion AThe place is important in demonstrating the evolution or pattern of Queensland’s history.

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.

Criterion BThe place demonstrates rare, uncommon or endangered aspects of Queensland’s cultural heritage.

The Mount Elliott Company Metallurgical Plant is significant in Queensland's history as the only recorded surviving evidence of an early electrolytic plant.

The laboratory remnants associated with the plant are architecturally uncommon, being made of ant bed adobe bricks.

Criterion CThe place has potential to yield information that will contribute to an understanding of Queensland’s history.

(Criterion under review)

Criterion FThe place is important in demonstrating a high degree of creative or technical achievement at a particular period.

The process was Mr H.S. Mackay's own invention and the plant was designed in London. It was the first plant of its kind ever built and Mackay supervised its construction at Cloncurry.

History

During 1924-25 the Mount Elliott Company and Hampden Cloncurry negotiated a scheme of amalgamation but this fell through when Mount Elliott acquired the Mount Cuthbert properties. 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 W.H. Corbould's vision of 1909 for amalgamation. But it was too late: funds were exhausted and prices were low (Hore-Lacey 1981:175). The company decided to use the English Mackay process to utilise the low-grade ores of the district. This was a new form of electrolytic smelting.

In 1926 the company started building the first 1,000 ton per year unit of a large electro-chemical copper treatment plant at Cloncurry on the outskirts of the town adjacent to the railway line. This comprised crushing, roasting furnace, leaching vats and a cell house section and was completed in April 1927.

The 6m diameter Mackay modified wedge furnace had seven roasting and one drying hearths. The furnace was connected to a Wilson pressure-type gas producer, which delivered gas to the roasting furnace as fuel to roast the ore. The furnace plant was enclosed in a steel building 11m by 11m and 12m high. In the leaching plant there were two reinforced concrete tanks 9m by 18m by 3m deep and four reinforced concrete solution storage tanks 9m in diameter and 3m deep. The plant for the electrolytic deposition of copper from the leaching solutions was in a two-storey steel building, 15m by 18m and 13m high. On the second level there were 24 wooded tanks 3.7m long, lined with lead, and containing electrolytic cells, cathodes, and anode bars. On the ground level were three wooden solution circulating tanks.

The power plant was located 4.5m from the electrolytic plant and housed in a steel building 9m by 18m by 9m high, with the boiler in a separate building. The plant included a Babcock and Wilcox boiler with a 37m steel chimney stack. A Belliss and Morcom compound engine was directly connected to a 400kw alternator. A spray cooling plant consisting of a concrete reservoir 18m by 18m and 1.5m deep with a series of spray pipes and nozzles operated from an electric centrifugal pump, was designed to cool 30,000 gallons of water an hour (QGMJ 15 Jan 1927:27).

However, before the plant was actually commissioned, instructions were received from London to close down without even a trial run. Apparently, the £128,000 construction expenses had been too high and it was considered that the capacity was insufficient for profitability (Hore-Lacey 1981:175).

It has been asserted (Blainey 1960:56) that the company had infringed a foreign patent, but cost factors may have influenced the decision to close the plant.

References:

Blainey, Geoffrey. 1960. Mines in the Spinifex, p.56.

Hore-Lacy, Ian (ed). 198 1. Broken Hill to Mount Isa, the Mining Odyssey of W. H. Corbould, p. 175.

Queensland Government Mining Journal, 15 January 1927, p.27.

Description

The place contains the remains of an electrolytic reduction plant comprising five groups of structures.

The primary crusher and ore dump group situated to the south comprise an ore dump site, earth loading ramp, concrete surfaces, tanks and building foundations. An iron flotation unit is located on the site (not in situ).

To the north are the concrete mounts and foundations of a wedge roasting furnace. These structures include a flue and iron chimney base and a vertical boiler alongside a concrete tank.

Adjacent to the west is a large concrete leaching vat 20m square and 3m in height, which was originally equipped with a gantry crane. The walls of the vat are supported by heavy concrete buttresses.

To the north are four circular leaching vats of concrete construction each 11m in width and 3m in height.

The northern group of structures is located alongside to south of the Cloncurry - Mount Isa railway. This group comprises concrete surfaces and foundations of the electrolytic works, a rendered brick flue and base of an iron chimney and three concrete tanks each approximately 15m² by 1.5m in depth.

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.

Plant equipment at the site includes a vertical boiler (no brand) and flotation unit (not in situ) (no brand).

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