Spinifex Ridge, Bamboo Creek District, East Pilbara Shire, Western Australia, Australiai

Regional Level Types
Spinifex Ridge	Project (Care and Maintenance)
Bamboo Creek District	Mining District
East Pilbara Shire	Shire
Western Australia	State
Australia	Country

A lease was granted to Kallenia Mines Pty Ltd in 2003. Hibernia Mines Limited part purchased the lease in 2004. It then changed its name to Moly Metals Ltd and completed a full purchase of the lease in 2006.

The company opened an iron ore mine at the location in November 2010, extracting ore from pits called Auton, Auton North-East, Gallifrey and Dalek. Ore was trucked to Port Hedland.

The company sold the mine to Mineral Resources in 2013 for $32.3 million Australian. In a strange deal that was always likely to end in tears, an estimated $3 million was further due when the mine was exhausted. However the company only continued mining until early 2014, then claimed $4.9 million from Moly Metals, which ended in court. There is no mention of the mine on Mineral Resources website at the time of writing (2016), and it is assumed the mine is still in mothballs.

Measured, Indicated and Inferred Resources 30 November 2012 is 5.5 Mt at 58% Fe.

The deposits are located in the Nimingarra Iron Formation of the Gorge Creek Group, bounded to the south by the Mount Edgar Batholith, and north by the Muccan Granitoid Complex.

The basal formation is the Duffer Formation of metamorphosed felsic volcanic rocks, with sub-ordinate fine grained amphibolite. Then the Apex Basalt, north facing pillowed mafic and ultramafic lavas 2 kilometres thick. Above this the Panorama Formation of discontinuous felsic volcanics and chert, then finally the Euro Basalt of metamorphosed pillowed tholeiitic and high Mg basalts and peridotitic komatiites. This is intercalated with thin bedded cherts, fuchsitic quartzites, and minor pelitic rocks.

Above this is the Nimingarra Iron Formation. At its base is pebble to cobble conglomerate grading upwards to sandstone, siltstone and shale. Then the disposition of banded iron formation, jaspilite, banded and Fe chert, and black carbonaceous shale.

The deposits are structurally complex with disconformities and disposition of sedimentary facies along growth structures. Early extensions have formed listric normal growth faults, and low angle detachment shear zones. The deposits sit in an upright to slightly overturned synclorium, wedged between the Coppin Gap Grandiorite to the south, and Muccan Granitoid Complex to the north.

The banded iron units strike east-west, dipping 70 to 90 degrees north. The lode style hematite is cross cut by north-west and north-east trending faults. Shear zones contain serpentine, talc, chlorite, carbonate and silica.

The deposits are hosted by jaspillitic banded iron formation, iron poor banded iron formations, and rare chert and shale. Alteration is not widespread apart from minor leaching forming a pale pink mudstone. Oxide mineralisation is hematite, goethite and limonite. No magnetite has been found. The gangue is silica and some clay.

The lode style mineralisation is massive hematite, vuggy and porous, lacking coherent banding. Specular hematite sometimes forms in the massive hematite. 55-58% Fe. Crustal style mineralisation forms well banded textures, highly fissile, lacks brecciation and re-cementation. Detrital style mineralisation is limited in extent consisting of re-cemented hematite fragments.

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