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The original Great Cobar Copper Mine structure dominates the entry to Cobar

Cobar Copper and Mining Heritage
Cobar Mining Heritage Centre
Headframe and winder from the Old Chesney Mine preserved in the Heritage Park
Stamper battery from the Mount Boppy Mine

Cobar Copper and Mining Heritage

Latitude -31.498086, Longitude 145.842218

Located in the Outback Region of NSW, nearest town Cobar

Source: Geological Survey of NSW

Source: www.resources.nsw.gov.au/__data/assets/pdf_file/0004/109192/cobars-mining-history.pdf

Source: www.csamine.com.au/csa-mine/

Source: www.cobar.nsw.gov.au

Link to Detailed Map

The local Aboriginal Ngiyampaa Tribe once inhabited the Cobar area prior to European Settlement. Their name for the area was "Kabbur". They have left evidence of their culture in aboriginal rock art at the Mount Grenfell Historic Site, located 60 kilometres west of Cobar. This site is managed by National Parks and Wildlife and visitors are welcome to come and view the art via walking tracks or to enjoy a picnic but there is no camping.

The Great Cobar Heritage Centre

Built in 1910 as the Administration Building for the Great Cobar Copper Mine, this imposing structure now houses the town's Heritage Museum which focuses on mining, agricultural and Aboriginal history. Open from 8.30am - 5pm weekdays and 9am - 5pm weekends and public holidays. Phone: (02) 6836 2448.

Cobar Miner's Heritage Park

Some of the objects which can be viewed at the park are: a two metre bronze sculpture of a miner, a restored stamper battery from the Mount Boppy Mine, a fifteen metre high poppet-head from the New Cobar Mine, a loader from the CSA Mine and the headframe and winder from the Old Chesney Mine.

Geology

The land around Cobar is flat and there are very few outcrops of rock. Geologists have drilled the region and have mapped the rocks making up the area. This is a simplified description of the component rocks.

The oldest recognised rock strata in the Cobar region are the Girilambone Group which is made up of Early Ordovician turbidite with thin chert units and mafic volcanics (a silicate mineral or rock that is rich in magnesium and iron), and a late Middle to early Late Ordovician turbidite with more significant and thicker chert units and basaltic volcanics. Analysis indicates that the basaltic volcanic rocks were erupted within an intraplate setting, probably as oceanic islands. Identifications of conodonts found within chert intercalated with pillow basalts of the Mount Dijou Volcanics indicate that they are of Early Ordovician age.

Deformation of the Girilambone Group occurred during the Late Ordovician to Early Silurian Benambran Orogeny. During that deformation the rocks were heated mostly to greenschist facies. Numerous granites intrude the Girilambone Group in Early Silurian and Early Devonian ages.

The Siluro-Devonian Cobar Supergroup unconformably overlies the Girilambone Group. Within the Cobar Basin the Cobar Supergroup is divided into the Nurri Group and the overlying Amphitheatre Group. The Nurri Group comprises basal conglomerates fining upwards into sandstones and siltstones and locally contain volcanic rocks. The Amphitheatre Group comprises finely bedded, deep-water turbidites.

Deformation of the Cobar Supergroup and underlying Girilambone Group occurred in the late Early Devonian. The Cobar style Au-Cu-Pb-Zn-Ag mineralisation, which occurs along the eastern edge of the basin and on the Kopyje Shelf (eg Mount Boppy mine), are considered to have been emplaced at that time. This mineralisation has been localised within high strain zones.

Mining History

Copper was discovered at Cobar in 1869 near a waterhole which became the site of the Great Cobar Mine. The relics of the Great Cobar Mine lie at the eastern end of Cobar and the former mine administration office now houses the heritage museum.

Since the discovery of base metals including; copper, gold, silver, lead, zinc and antimony at Cobar "Copper City" the mining of these resources has declined and grown at the mercy of metal prices. The area also suffered from lack of water, rail transport and local timber for mine construction and smelting.

The area is very rich in base metal and continuing exploration and new technology over the past 140 years has expanded the reserves in the area leading to re-opening of closed mines when metal prices improve and mothballing when prices retreat. This has occurred on a constant basis and has caused the population of Cobar to expand to as many as 10,000 and contract to as few as 600 as a result.

The CSA Mine

The CSA mine is located 14 kilometres northwest of Cobar, along the Louth Road. Mining has occurred intermittently on the CSA (Cornish, Scottish, Australian) lease since discovery in 1871 It is operated by Cobar Management Pty Ltd (CMPL) Since 1965 the mine has extracted substantial quantities of zinc, lead, silver and copper, but today, CSA Mine focuses on mining copper, with a silver co-product.

The underground mine produces over 1.1 million tonnes of copper ore and produces in excess of 185,000 tonnes of copper concentrate per annum. The concentrate contains approximately 29% copper metal and is exported to smelters in India, China and South East Asia. Operating 24 hours a day, seven days a week, CSA Mine provides direct employment for over 300 people, the majority of whom are based in the local township of Cobar.

In its natural state, mineral compounds such as copper are found surrounded by rock. Combined, this group of materials are called 'ore', and typically, ore contains only 0.5% to 2.0% copper. At CSA Mine the ore grade averages over 6% and with some as high as 12%, making it one of the richest copper ore deposits in the world.

The most common copper minerals are Chalcopyrite, Bornite and Malachite. The copper mineral mined at CSA Mine is Chalcopyrite (a copper iron sulphide), which has a golden yellow appearance. As a processed metal, copper is red, with a bright metallic lustre.

New Cobar Open Cut Gold Mine
New Cobar Open Cut Gold Mine

Exciting times lie ahead for CMPL with a multi-million dollar shaft extension project already approved as well as various other projects that will significantly increase the life of the mine and lower mining costs. As well the company holds many exploration permits in the region.

The Endeavor Mine

The Endeavor Mine, Located 47 kilometres north of Cobar in central western New South Wales, is the largest zinc, lead and silver producer in the region.

First brought into production in 1983 as the Elura Mine at a cost of $270 million, The Endeavor orebody is similar to others in the Cobar Basin in that it has the form of massive vertical pillars. The Mine is an entirely underground operation accessed by traditional shaft haulage with concentrator, drying, storage and rail facilities on the mine lease.

In extracting the mineral, ore is taken from the surface stockpile and placed in a concentrator where froth flotation separates the particles of valuable zinc, lead and silver materials from the waste. Metal concentrates are then dried for rail freighting to smelters in Port Pirie in South Australia and overseas, predominately Japan.

Endeavor is currently producing at a rate of 720,000 tonnes of ore per annum producing 85,000 tonnes of concentrates and 50,000 tonnes of lead concentrates. Endeavor also produces 24,000kg of silver contained in the lead concentrates.

Endeavor currently has mine reserves in excess of 6.0 million tonnes and is actively exploring in and around the mine to further add to the resource base.

Peak Gold Mine

Peak Gold Mine is a wholly owned subsidiary of New Gold. The Peak operation currently consists of five producing gold and copper deposits that are being mined from underground to provide mill feed to a central gold/copper processing plant. These deposits comprise part of the greater Cobar Gold Field, a 10km long belt of historic gold and copper mines that extends northwards from the Perseverance-Peak Gold mine to the Tharsis working, immediately north of Cobar township. The Cobar Gold Field is located on the eastern margin of the Cobar Basin and has produced in excess of 3 million ounces of gold and 200,000 tonnes of copper since mining commenced in 1870. The ore bodies currently being mined by Peak Gold Mines are Peak, New Occidental, New Cobar, Perseverance, and Chesney.

Other mines in the area include Mt Boppy Gold Mine currently closed; The Wonawinta Silver Project currently under development and the Hera Gold and base metal deposit an evolving copper deposit at Nymagee with the potential that the Nymagee mineralisation may evolve into another 'Cobar Giant' similar to the world class CSA copper deposit located approximately 100km north-west along strike.

This view is from the Fort Bourke lookout. The broad white bar showing on the New Cobar Open Cut mine wall opposite the viewing platform is a quartz vein. The copper-gold mineralisation which was mined from the open cut was intruded by many quartz veins which were probably related to the host shear zone which controlled the emplacement of mineralisation in the New Cobar Copper-Gold Deposit.  This is a particularly large vein or reef which may have hosted gold, hence the adits developed along its extent. There was possibly stoping of the vein where gold-rich shoots occurred.

Fort Bourke Hill Lookout & New Cobar Open Cut Gold Mine

Turn off the Kidman Way, 2kms south of Cobar and take a sealed road up to Fort Bourke Lookout (300 metres above sea level) to view Cobar and its surroundings. The rich Cobar mineral belt is clearly visible in a straight line from North to South (line up the head-frames).

Fort Bourke Hill is the historical site of Cobar's first gold mine, the New Cobar Gold Mine. Peak Gold Mines operates an underground mine at Fort Bourke and visitors can gain a spectacular view of the pit and entrance to the underground mine from the viewing platform. The open cut is 380 metres in length, 200m wide and 150m deep. At the base there is an entrance to the underground part of the mine and you can see trucks regularly entering and leaving the mine day and night.

The lookout is a fenced, well constructed platform on the eastern side of the open cut. There is a door which can be locked, so check at the Cobar Heritage Centre (02) 6836 2448 to see if it is open to the public.

Getting There

Cobar is situated on the crossroads of the Barrier Highway, running east/west and the Kidman Way, running north/south. It lies in the Outback NSW area between Nyngan and Wilcannia.


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