Mount Cassiterite, Wodgina, Abydos Station, Port Hedland Shire, Western Australia, Australiai

Regional Level Types
Mount Cassiterite	Mountain
Wodgina	- not defined -
Abydos Station	- not defined -
Port Hedland Shire	Shire
Western Australia	State
Australia	Country

Mount Cassiterite is an open cut pit and consists of pegmatites, one kilometre south of the Wodgina pegmatites. As a modern mine it is viewed as one deposit, however the two areas show different types of pegmatites.

Mount Cassiterite covers an area of 1.1 x 0.8 kilometres, as a series pegmatite sheets, dykes, and irregular offset structures. It is hosted by metasedimentary fine grained psammite, and thick interbedded pelite, with minor quartzite and chert.

There are two main sets of stacked pegmatite sheet, 5 to 12 metres thick, 2 to 100 metres long, dipping 20 to 25 degrees south-east, with a partial roll-over dip 15 to 20 degrees south-west. The sheets are interconnected by near vertical dykes, trending north-west to south-east, and north-east to south-west, by irregular keel like structures, and thin stringers of pegmatite, all emplaced at the same time. There is a third pegmatite structure lower down, but reaches a depth of up to 400 metres from the surface.

The pegmatites are albite-spodumene type, with some K feldspar, and minor muscovite, as near homogenous bodies. The texture is massive to comb, with little zonation. Spodumene and perthitic microcline are dominant in a matrix of fine to medium grained quartz, albite, and muscovite. Spodumene crystals are aligned perpendicular to the pegmatite contacts, exhibiting 'pull-apart' structures. Zonation is limited to a finer grained border unit of microcline crystals.

The main economic ore is wodginite and cassiterite, with sub-ordinate manganotantalite and manganocolumbite, and an altered assemblage of stanniferous microclite, with trace calciotantite.

Other Regions, Features and Areas containing this locality

References