Granny Venn Gold Mine (Auntie Nellie; Jenny Venn; CSR; G-VAN), Menzies, Menzies Shire, Western Australia, Australiai

Regional Level Types
Granny Venn Gold Mine (Auntie Nellie; Jenny Venn; CSR; G-VAN)	Mine
Menzies	- not defined -
Menzies Shire	Shire
Western Australia	State
Australia	Country

The Granny Venn Gold Mine is 8 kilometres north-east of Menzies, and 500 metres south-east of the Goldfields Highway. It consists of two near adjacent pits, the northern called Granny Venn and the south Auntie Nellie.

The deposit was discovered in the late 1990's by Money Mining NL, who then entered into a joint venture with Paddington Gold Mines Pty Ltd, to develop two shallow oxide ore pits to a depth of 45 metres, with the ore processed at the Paddington mill near Broad Arrow. The project obtained approximately 60 000 ounces of gold at an average grade of 3.54 g/t from 532 000 tonnes of ore, across 1999 to 2000. A remnant stockpile of lode grade ore was removed from the site in 2012, and sent to the Paddington mill.

The deposits are part of a 17 kilometre structural corridor, with Granny Venn at its southern end. This is a narrow corridor of sandstone, mafic, ultramafic and felsic rocks, between two large granite bodies, with a phlogopite alteration rim. The granitic rocks are strongly altered to tremolite-actinolite, plagioclase, K-feldspar, and quartz, forming boudins within chlorite serpentinites with variable amounts of tremolite and talc.

The direction of mineralisation is north north-east, in contrast to the structural elements in the pits which head east-west. The serpentinites are strongly foliated and show intense and penetrative southerly movement. The shear zones are associated with drag folds of gently dipping foliation, and develop into detachment planes, associated with south verging recumbent folds.

Irregular granitic intrusion sheets are folded and boudinaged, described as looking like a chocolate tablet in the horizontal plane. Vertical shortening is evident. The serpentinite at the margins of the granitic rocks have been altered to phlogopite schist up to 1 metre wide.

Mineralisation is associated with the north-south to north north-west to south south-east trending structures being truncated by the north north-east to south south-west trending Springfield-Venn Fault. The highest grade gold is found where dacites have been impacted by the structures resulting in brittle fracturing, which hosts the gold and sulphides. Gold is associated with pyrite.

Exploration companies have targeted three areas near the pits. The Jenny Venn prospect is 2 kilometres south of the pits showing laminated quartz-tourmaline veins containing coarse nuggety gold. The CSR prospect is between the two pits, and is named after Colonial Sugar Refineries (CSR) who drilled it in the 1980's. Shallow north trending shoots from the Granny Venn pit have also been investigated.

The present exploration company calls the area the G-VAN project.

Other Regions, Features and Areas containing this locality

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