Cornishman Gold Mine, Southern Cross, Yilgarn Shire, Western Australia, Australiai

Regional Level Types
Cornishman Gold Mine	Mine
Southern Cross	Town
Yilgarn Shire	Shire
Western Australia	State
Australia	Country

The Cornishman Gold Mine is 5 kilometres south-east of Southern Cross, and about 500 metres south of the Polaris South Gold Mine.

Before modern mining the site saw limited development, mainly by prospectors and tributing parties with long periods of inactivity from 1903. The earliest report found was 1908, when the mine was being developed by E.J. Pearce and John Henry Cooper. Within a year, Cooper had bought out Pearce. A company was formed in Adelaide in 1910 to purchase the mine from Cooper for 4500 pounds (GML 776 formerly GML 582)24 acres. The main shaft was down to 120 feet on a lode 10 feet wide.

Little was heard of any activity by the company at the mine site subsequently. Cooper appears to have retained control, and spasmodic production was seen from him until the outbreak of World War Two.

From 1911 to 1947 the site produced 1077 tonnes of ore for 1111 ounces of gold at 1.03 g/t.

The mine is owned by the Coronation Gold Mining Company in the late 1930's, but mining is being conducted by tributers. In 1947, brothers Frank and Tony Calzoni discovered a rich small leader, 100 feet north of the main shaft.

Modern development began with the discovery of the Double O lode by Troy Resources by soil sampling in 1987. Further exploration by 1992 had defined a resource of 542 000 tonnes of ore at 3.60 g/t. Also found along the strike in 1993-1994 was two small supergene zones called the Northern and New Find deposits. Troy formed a joint venture with Sons of Gwalia Ltd, and in 1997 the larger Triple O lode was uncovered to the east. This has an estimated resource of 1.5 Mt at 4.87 g/t. Subsequent mining by the joint venture in the late 1990's formed a large and long open pit, partially refilled with waste rock in the centre of the pit as a low plateau. In 2015, Hanking Ltd re-started open pit mining at the location.

The mine is located in the Southern Cross Greenstone Belt. There are four types of gold mineralisation at Cornishman:
1. Shear zones in tremolite-chlorite schist, with biotite-diopside-pyrrhotite-pyrite alteration, with most of the ore in the supergene zone as quartz veins hosting gold. (eg. Double O Lode)
2. BIF hosted lodes with associated calc-silicate veins and alteration (eg. Triple O Lode)
3. Quartz stockwork with weakly developed diopside-chlorite-biotite alteration, within shear zones in amphibole (eg. New Find Lode).
4. Quartz supergene mineralisation above a shear zone hosted by ultramafic rocks (eg. Northern Lode).

All mineralisation is sulphide poor with minor pyrrhotite, pyrite and chalcopyrite. The alteration envelope at Double O varies from 50 metres in fresh rock to 10 metres depending on depth in the saprolite above.

The gold bearing regolith contains a dark green lower saprolite, and pale yellow green upper saprolite. Above this is overburden 2 to 15 metres thick of mottled kaolinite with quartz, hematite, trace magnetite.

Other Regions, Features and Areas containing this locality

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