Mount Marion pegmatites, Spargoville, Coolgardie Shire, Western Australia, Australiai

Regional Level Types
Mount Marion pegmatites	Pegmatite Field
Spargoville	- not defined -
Coolgardie Shire	Shire
Western Australia	State
Australia	Country

Spodumene pegmatites (LCT-type), hosted by amphibolites.
Located about 50 km south of Kalgoorlie.

The Mount Marion pegmatites are about 30 kilometres south-east of Coolgardie between the Coolgardie-Esperance Highway and the Kalgoorlie-Kambalda Road. Access to the pegmatites at present (2013) is virtually impossible due to active gold mining in the immediate area.

They are the first recognised unzoned albite-spodumene pegmatites in Western Australia. They consist of a series of pegmatites running north-west to south-east for about 3 kilometres. The southern most is called No 4 pegmatite on MC60, then MC 15/4476 lease, MC 27, MC 24 called the No1 and No2 pegmatites, MC 26, MC 25 which contains No 2 West Pegmatite, and No 3 pegmatite about 500 metres further north-west and is the northern limit of the pegmatite field.

The pegmatite was first discovered while conducting a regional mapping exercise in 1913 by C.S. Honman. Hampton Plains Mining syndicate employing two men was mining the pegmatite in 1956, by blasting several cross-cut trenches. The largest at this time was 6 metres long, 2 metres wide, and 1.5 metres deep. The pegmatites were mapped in detail by J. Lalor for Western Mining Corporation in 1960. Between 1960 to 1964 the same company explored the area, and conducted further drilling between 1971 to 1986. No mining took place and the leases were surrendered.

Pegmatite No 1 forms a flat sheet averaging 17-21 metres thick, dipping 15 degrees to the west, and has eroded into two masses a total length of 335 metres. The pegmatite has a homogeneous granitic texture of quartz, microcline, albite and muscovite, with some pale green to white spodumene crystals up to 30 cm in length. A thin band of cleavelandite occurs near the hanging wall and footwall, with holmquistite along the hanging wall contact.

Pegmatite No 2, similar to No 1, is 330 metres long and dips 30 degrees to the west. Pegmatite No 2 West forms a V-shaped outcrop in a north-south direction and is 30 metres wide.

Pegamtite No 3 is a flat lying sheet, 4 to 14 metres thick, with a strike length of 640 metres. It contains spodumene crystals up to 1 metre in length. The pegmatite has a core of quartz-spodumene-albite-muscovite
containing 30-50% spodumene. The next zone is microcline-quartz-plagioclase-muscovite wall zone. Small sub-centimetre columbite-tantalite crystals are found with the albite in the core.

Pegmatite No 4 is similar to No1. It outcrops as a narrow curved vein north-south, 6-8 metres thick, dipping 10-25 degrees to the west, unzoned and contains spodumene.

Note: The Mindat co-ordinates are approximate.

Other Regions, Features and Areas containing this locality

References