Cox-Crusader Gold Mine, Agnew Goldfield (Lawlers), Leonora Shire, Western Australia, Australiai

Regional Level Types
Cox-Crusader Gold Mine	Mine
Agnew Goldfield (Lawlers)	Ore Field
Leonora Shire	Shire
Western Australia	State
Australia	Country

The Cox-Crusader Gold Mine is an open pit, 11 kilometres south south-west from the Agnew Hotel.

The Cox deposit was discovered by Asarco Australia Ltd in 1988, and developed an open pit, obtaining 177 000 tonnes of ore at 5.6 g/t.

The northerly plunge extent of the ore body crossed into the Western Mining Corporation tenements. They conducted underground mining, obtaining 1.3 Mt at 9.6 g/t yielding 374 000 ounces.

The deposit is down trend from the Redeemer deposit 3 kilometres to the north, on the western limb of the Lawlers Anticline, consisting of tholeiitic pillow basalt, interflow sediments and sulphidic carbonaceous shale. The basalt contains interstitial quartz, chlorite, epidote, magnetite, and minor pyrrhotite, pyrite and chalcopyrite.

This is overlain by 40 to 60 metres of serpentinized and carbonated dunites and orthocumulate peridotites, sheared komatiite flows, high Mg basalt, and shale, with felsic and gabbro intrusives, capped by a sheared mafic conglomerate.

There is an alteration assemblage in the 40-60 metre thick dunite and peridotite of magnesite-antigorite-talc-dolomite-ankerite-magnetite-chlorite.

The alteration assemblage in the overlying 30 to 110 metre thick komatiite flows is amphibole-talc-chlorite-magnetite-carbonate-antigorite.

Separating the two is the Pilgrim Shear Zone, 10-14 metres thick, containing wedges of talc-magnesite-carbonate-biotite alteration, and an upper limit of mylonisation, accompanied by amphibolite-talc-chlorite-magnetite-carbonate-antigorite alteration.

Overlying this is 80 metres thick volcano-sediments, containing high Mg basalt, interflow sediments, shales, cut by felsic and gabbro intusives, and capped by 110 metre sheared mafic conglomerate.

Gold is hosted with a 20-30 degree north trending plunge associated with a flexure in the ultramafic basalt contact. The ore body is multiple discrete lodes.

The lodes are 2-30 metre thick, and extend for 30 metres down dip, with mineralisation in 3 parallel lodes, with high grade gold in pods in flexures. These are linked by lower grade limbs. The native gold is very finely disseminated, and associated with epidote-magnetite-chlorite-actinolite-biotite alteration, with scheelite, Bi tellurides, and minor chalcopyrite, enriched with Bi, Se, Te, Mo and W.

The Cox deposit shows at the surface as a strong co-herent anomaly covering 15 000 square metres.

Other Regions, Features and Areas containing this locality

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