Projects - Australia

Whim Creek VMS Project

The Whim Creek VMS Project is located adjacent to the Northwest Coastal Highway, mid way between Karratha and Port Hedland in the Pilbara Region of Western Australia. The copper-zinc-lead-silver-gold deposits are hosted by Early Archaean (3560-2770 Ma) metavolcanic and metasedimentary sequences that surround large domal granitoid masses. Volcanogenic massive sulphide (VMS) deposits are confined to the Whim Creek and Sholl volcanic belts.  The Whim Creek volcanics crop out as a continuous arcuate belt some 85 km long and 5 to 10 km wide. Significant VMS deposits occur at Mons Cupri, Whim Creek, Salt Creek and Balla Balla. The Evelyn deposit, located 35 km to the south, occupies a volcanic horizon believed to be stratigraphically equivalent to the Whim Creek volcanics.  Numerous other workings and geochemical and geophysical anomalies await thorough evaluation.

Historical Operations

The Whim Creek was mined from 1889 to 1964 and 112,000 tonnes of supergene-enriched ore averaging 10.1% Cu was recovered.  In 1999, remaining oxide resources at Whim Creek and Mons Cupri were estimated to be 1.0Mt @ 1.5% Cu and 13.0Mt @ 1% Cu, respectively. From 2005 to 2009 Straits Resources operated an advanced heap leach and SX-EW copper oxide plant producing over 35,000 tonnes of copper cathode.

Exploration & Mining Leases

Tenement	Owner	Grant Date	Area (Hectares)	Comments
M47/236	Straits (Whim Creek) Pty Ltd	27-Jul-90	966.30
M47/237	Straits (Whim Creek) Pty Ltd	27-Jul-90	412.60
M47/238	Straits (Whim Creek) Pty Ltd	27-Jul-90	983.20
M47/443	Straits (Whim Creek) Pty Ltd	2-Jun-98	40.55	Not subject to State Royalty
E47/924	Straits (Whim Creek) Pty Ltd	21-Apr-05	5,011.00
E47/976	Straits (Whim Creek) Pty Ltd	21-Apr-05	11,380.00
E47/1088	Straits (Whim Creek) Pty Ltd	5-Aug-04	1,493.00
L47/36	Straits (Whim Creek) Pty Ltd	19-Aug-98	6.30
G47/1233	Straits (Whim Creek) Pty Ltd	Pending	45.80	Pending
M47/323	Raymond Butler	4-Jun-93	363.30	Transfers to Whim Creek pending - 2.5% Net Profit Royalty on production >1mt
M47/324	Raymond Butler	4-Jun-93	484.20

Infrastructure

Existing infrastructure at the Whim Creek site includes a 1Mtpa crushing circuit, haul roads, a power distribution network, water bores, mine offices, workshops and accommodation village. In addition, the site is located adjacent to the Northwest Coastal Highway, a gas pipeline and high voltage power grid.

Future Sulphide Operations

Established sulphide resources (measured, indicated and inferred) in the Whim Creek VMS Project area amount to 11.6 million tonnes @ 0.9% Cu, 1.4% Zn and 0.4% Pb. A preliminary production concept incorporates open pit optimisations at Whim Creek, Mons Cupri and Evelyn (Liberty-Indee) and underground mining at Salt Creek.

In July 2006, COMO Engineers undertook a scoping study to estimate the capital cost of a 500,000 tpa copper concentrator and related infrastructure. The sulphide processing facility would be capable of producing separate copper and zinc sulphide concentrates with consideration given to lead concentrate if proven to be economic. The concentrator was expected to produce in the order of 10,000 to 15,000 tpa of copper metal equivalent.

In January 2010, Venturex announced its intention to target high grade massive sulphide zones within and around existing low grade resource envelopes.  Should resources of sufficient tonnage and grade be identified, the Company will consider the development of a smaller mill with the capacity to treat higher grade ores.

Priority Resource Development Targets

Mons Cupri

This is the largest known sulphide resource in the Whim Creek VMS Project area. The deposit lies within the upper parts of the Mons Cupri Volcanics. It consist of an ovoid lens (250 m by 400 m) of stratiform Zn-Pb-Cu sulphides, underlain by stockworks, stringer and disseminated Cu-Zn mineralisation within a large pipe-like alteration zone. There are a number of higher grade massive sulphides and stinger sulphide zones that have potential to provide substantial zones of high grade ore.

A continuous zone of high grade sulphide located down-dip and to the west of the Mons Cupri oxide open pit provides an immediate opportunity for a near-surface high grade resource, amenable to open pit mining.

Mons Cupri Northwest

Significant zinc, lead and copper mineralisation (including WMD060: 5.7m @ 7.4% Zn, 2.4% Pb and 1.4% Cu) has been intersected at relatively shallow depths directly west of the Mons Cupri Northwest pit. These zones are outside existing resource estimates. Further exploration will target down dip extensions of zinc-lead mineralisation and footwall zones of stringer copper mineralisation.

Whim Creek

Copper-dominant massive sulphide mineralisation extends below and to the south of the Whim Creek oxide pit.  Stringer copper sulphide mineralisation also occurs in the footwall and is largely untested.  The Company will re-evaluate high grade sulphide mineralisation and design a drill program to confirm and extend known resources.

Salt Creek

Salt Creek is the largest known VMS deposit in the Salt Creek Belt, approximately 17km north of Whim Creek. It consists of a pair of south-east plunging ribbon-like shoots of zinc and copper-zinc massive sulphides.  As previously reported (ASX announcement 20 August 2009), total JORC sulphide resources at Salt Creek amount to 1.83 million tonnes @ 1.4% Cu, 3.8% Zn and 1.2% Pb. This includes a higher grade zinc-lead component of 846,000 tonnes @ 7.7% Zn, 2.4% Pb, 90g/t Ag and a higher grade copper component of 1.02 million tonnes @ 2.0%. As indicated in the Salt Creek cross-section, zones of high grade mineralisation are well developed. Venturex intends to remodel the resource using a higher grade envelope, and identify lateral and depth extensions of favourable shoots.

Long-section of high grade Zn-Pb lenses at Salt Creek
(parallel copper lenses not shown)

Balla Balla

Recent exploration at the Balla Balla VMS prospect has identified a significant new massive sulphide lens. The Balla Balla VMS prospect lies 2 kilometres and 6 kilometres east of the West Balla and Salt Creek VMS prospects respectively, and is interpreted to lie within the same prospective horizon as Salt Creek. Recent exploration drilling intersected a steeply south-dipping, massive zinc-lead sulphide lens over a strike length of greater than 400 metres with a vertical extent of greater than 200 metres containing some copper sulphide rich mineralisation within the horizon. The lens is open at depth and along strike in all directions.

West Balla

The West Balla VMS prospect was discovered by in February 2008 via reverse circulation drilling. West Balla is hosted within steep dipping tuffaceous sediments beneath a hanging wall of meta-volcanics. Better intersections at the West Balla project include 4 metres @ 15.1% Zn, 4.6% Pb and 5m @ 1.1% Cu. The mineralisation is open along strike.

East Balla

East Balla is located approximately 1 kilometre east of the Balla Balla VMS deposit, in an area of sparse outcrop. The prospect was identified in 2007 from an outcrop of massive chalcocite in a small gossan returning an assay of 18% Cu, 570ppm Zn and >1% Pb. The East Balla area is known to contain the typical Balla Balla stratigraphic section with intersections of massive sulphide including 2.1 metres @ 6.93% Cu and 0.8m @ 17% Cu.

Liberty-Indee

The Liberty-Indee Project, located approximately 30 kilometres south of Whim Creek in the Pilbara Region of Western Australia, is believed to be a volcanic-associated massive sulphide (VMS) discovery.

Detailed mapping has delineated a distinct geological horizon characterised by bi-modal volcanism (basalt/dacite/rhyolite) and numerous sulphide horizons, along a strike length of at least 12 kilometres.

Geophysical fixed loop and down hole electromagnetic data located a number of conductor targets below the Evelyn workings and to the north of Evelyn – a total strike distance of approximately 900m-1,000m.

Initial RC drilling results at Evelyn included: 19m @ 2.6% Cu, 5.1% Zn, 0.5% Pb, 61g/t Ag, 1.3g/t Au and 10m @ 6.4% Cu, 2.4% Zn, 67g/t Ag and 0.86g/t Au.

Commencing in mid-2009, a new exploration program focused on deeper targets beneath the Evelyn workings; a significant untested structural corridor to the south of Evelyn; and a number of untested geochemically anomalous gossans, to the north and northeast of Evelyn.

Results of the mid-2009 program were highly encouraging, with broad zones of massive sulphide intersected in several RC holes. At Evelyn, the strike length of economically significant mineralisation was extended believed to at least 400 metres, with individual lenses up to 16 metres thick and 240 metres in strike length.

			Sulphide Intersection
Hole	Dip	Az	From	To	Width	ETW*	Cu%	Zn%	Pb%	Ag g/t	Au g/t	Cu% eq#	Ref
JER042	-60	130	147	150	3	2.4	0.96	7.45	0.63	33.30	0.19	3.87	1
			183	186	3	2.4	0.32	1.42	0.09	10.00	0.04	0.89	2
JER044	-60	130	61	81	20	16.0	3.43	6.47	0.38	65.00	1.73	7.17	3
JER046	-60	130	37	54	17	13.0	4.16	8.70	0.56	66.50	1.03	8.23	4
JER047	-60	130	78	93	15	12.0	2.37	3.75	0.28	45.00	0.84	4.52	5
			78	81	3	2.4	3.95	9.05	0.53	62.00	1.72	8.50	6
			86	93	7	5.6	3.30	3.75	0.26	63.50	1.04	5.73	7
Average weighted grade of intercepts 3,4,6,7							3.71	7.04	0.43	65.00	1.37	7.42

^*ETW = Estimated True Width
^#Cu % eq = value of all metals expressed at copper only (metal prices as at 3/7/09)

An agreement with the Ngarluma Community cemented in 2007 allows for exploration inside heritage cleared areas. A working relationship with the Pastoralist has also been fundamental to progress.

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