Donnelly River graphite deposit, Manjimup Shire, Western Australia, Australiai

Regional Level Types
Donnelly River graphite deposit	Deposit (Abandoned)
Manjimup Shire	Shire
Western Australia	State
Australia	Country

An historic graphite mine.

This was reported by the Department of Mines in 1894, and again in 1916. Located 20 kilometres west of Manjimup, about one kilometre south-west of One Tree Bridge, and just north of Henwood Road in thick forest. The site may contain a washing plant ruin, collapsed adit, and at least three timbered shafts.

In 1888, a Busselton syndicate explored the site, but the low price for graphite at the time made it uneconomic. Early 1894, A. Knox-Brown discovered more graphite close to the old find. An adit was driven into a ridge, along with several shallow shafts, and small open cuts. Samples were sent to several overseas firms, however the material was assessed as valueless due to its pale colour and earthiness.

In 1902, A.A. Carlier attempted unsuccessfully to float a company in London to mine the deposit. In 1905, a number of leases and local syndicates were formed, but little mining or developmental work was undertaken. H.J. Saunders tried unsuccessfully to float a company in New York. The Donnelly River Graphite Company went into voluntary liquidation this year, after finding no market for the material. Heinrich Sillem had developed the mine for the company, and suffered considerable financial losses from the mine's failure.

R.G. Clark then held the leases from around 1909 to at least 1916. Apart from deepening an existing shaft, no more work was done, the site abandoned. The total area of leases covered approximately 3 miles north-south and 1.5 miles east-west. The original workings are in the south-east corner of this area, and later workings in the centre.

Knox-Brown's drive into the ridge revealed three beds of graphite; the first 28 feet thick, followed by 13 feet of schistose rock containing a small bed 1 foot 6 inches thick, and then a third bed 8 feet thick.

The graphite area is in an east-west shear zone, bounded to the north where the gneissic rocks contact greenstone dykes, and the south by magmatic porphyry granite with dolerite veins. The graphite forms beds, grey when dry and black when wet, ranging from almost pure clay to seams and bunches of fairly high quality. The wall rock is more siliceous with disseminated graphite scales. Generally it is amorphous graphite intermixed with clay and minute graphite flakes.

The area included historically a 60 foot shaft, the adit described above, and several prospecting shafts and small open cuts. The quality of the material was said to improve with depth, but could not be verified by the geologist in 1916, due to the 60 foot shaft being full of water.

18 tonnes was produced between 1940 to 1943. O'Brien and the Giacci Brothers Pty Ltd explored the site in 1984 to 1986, then Cable Sands (W.A.) Pty Ltd 1986 to 1988.

There are five graphite lodes. The most northern is Top Lode, not discovered until 1985, 3 to 4 metres thick and 40 metres in strike of high grade graphite. The southern most is Creek Lode also discovered in 1985 of clayey low grade graphite. The North-West and Centre Lodes are a single body 130 metres long and 4 to 10 metres thick. The Lower Lode is 6 to 11 metres thick and strikes for 100 metres, containing 18 metres of good graphite, and some contamination of soil and clay in the upper portion. The deposits are on the Hanging Wall layer of hard ferruginous duricrust.

Please note the Mindat co-ordinates could be approximate. A visit to the site listed based on maps in written references, failed to locate any evidence of mining, although it could be hidden within thick karri forest.

References

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