Anax has entered into an earn-in agreement with Venturex Resources Limited to develop the Whim Creek Project, Pilbara region, Western Australia. Anax intend to apply smart sorting technology to generate a pre-concentrate for toll treatment offsite.
- Combined JORC 2012 Resources of over 6.9Mt at 0.93% Cu and 1.83%Zn with precious metal credits.
- Historical resources to be updated to JORC 2012 increasing the Projects resource base.
- Review of available drill core and preliminary test work suggests the ore is well suited to the application of sorting technology.
- Significant near-mine exploration potential, building on recent and historical exploration.
- Well maintained site with viable existing infrastructure.
- Proximity to ports and potential toll treatment plants.
The Whim Creek Copper-Zinc Project is located approximately 120km south-west of Port Hedland in the Central Pilbara Region of Western Australia. The map illustrates the location of the project in relation to neighbouring tenure and local infrastructure, including Port Hedland, Karratha and the Great Northern Highway.
Whim Creek Project Location Map
Regional GSWA Geology and tenure at Whim Creek Project
Within the Project are four main prospects, namely Whim Creek, Mons Cupri, Salt Creek and Evelyn, where structurally controlled, volcanic hosted massive sulphide (VHMS) style, copper-zinc-lead mineralisation has been targeted and/or resources defined. Salt Creek, Whim Creek and Mons Cupri occur within volcanicastics and sediments of the Bookingarra Group, part of the Archean Whim Creek Basin. The Evelyn deposit, 25km to the south, occupies the contact between sandstones and ultramafics of the De Grey Group in the Croydon Anticline structure of the Mallina Basin, considered to be laterally equivalent to the Whim Creek Greenstones.
The Archean granite-greenstones of the Whim Creek tenure are highly prospective for gold mineralisation. Deep seated, mineralising structures bound the tenure to the north-east and south-west providing ~40km of prospective strike along which numerous gold targets have already been identified for exploration.
Venturex defined JORC 2012 compliant Mineral Resource Estimates for Mons Cupri and Salt Creek, updated in 2018. The Mons Cupri Mineral Resource makes up the majority of the defined JORC 2012 Mineral Resources with 5.1Mt at 0.9% cu and 1.0% Zn, and will become the focus of Anax’s development proposal. The Salt Creek Mineral Resource contains 1.9Mt @ 1.0% Cu and 4.2% Zn and completes the Project’s Mineral Resource inventory.
Mons Cupri JORC 2012 Resource Estimate
Salt Creek JORC 2012 Resource Estimate
Whim Creek Project JORC 2012 Mineral Resources Summary (Venturex, March 2018)
SRK Exploration Target for the Whim Creek deposit as at 1 July 2020
SRK Exploration Target for the Evelyn deposit as at 1 July 2020
- An Exploration Target is a statement or estimate of the exploration potential of a mineral deposit in a defined geological setting where the statement or estimate, quoted as a range of tonnes and a range of grade, relates to mineralisation for which there has been insufficient exploration to estimate a Mineral Resource. The potential quantity and grade of the Exploration Target is conceptual in nature, there has been insufficient exploration to estimate an additional Mineral Resource and it is uncertain if further exploration will result in the estimation of an additional Mineral Resource.
- The upper and lower grades of the Exploration Target estimate do not necessarily correspond to the upper and lower tonnages, nor do the upper and lower grades for each element necessarily correspond.
- The Exploration Target is reported on an in situ basis based typically on confidence of geological and grade model continuity.
- The Exploration Target does not have demonstrated economic viability, nor have any mining Modifying Factors been applied.
- Bulk density applied: oxide ore - 3.0, transitional ore - 3.50, and fresh ore - 4.15.
Tonnages are reported in metric units and grades are given in percentages. Tonnages and grades are rounded appropriately. Rounding, as required by reporting guidelines, may result in apparent summation differences between tonnes, grade and contained metal content. Where these occur, SRK does not consider these to be material.
The discovery of gold and copper in the Whim Creek area in the early 1880s led to a period of underground, artisanal mining until 1912, during which high grade copper-gold ore shoots were targeted.
Systematic exploration by various companies in the 1960s, including Texasgulf, defined the known VHMS deposits of the Whim Creek Greenstone Belt, namely Whim Creek, Mons Cupri and Salt Creek.
Straits Resources acquired the Project in 1996 and commenced mining in 2005. Oxide copper ore mined from the Whim Creek and Mons Cupri open pits was crushed and placed on a purpose-built heap leach facility located 3km north east of the Mons Cupri pit. Approximately 67,000t of copper cathode was produced through an SX-EW treatment facility until 2009.
Venturex acquired the Whim Creek Project from Straits Resources in 2010, intending to use Whim Creek as a central processing hub for their existing Evelyn and Sulphur Springs deposits. The 2012 Sulphur Springs Feasibility Study, 2012, proposed locating the central processing plant at Sulphur Springs and transporting ore from the satellite deposits such as Mons Cupri and Salt Creek. This became Venturex’s preferred development proposal. However, Venturex has continued to develop the Whim Creek project, defining JORC 2012 compliant resources at Mons Cupri and Salt Creek, updated in 2018.
In March 2014, Venturex entered into an agreement with a private company, Blackrock Metals Pty Ltd (“Blackrock”), for the reprocessing of existing heap leach pads to recover copper metal through a small, refurbished, 5,000 tonne per annum, SX-EW treatment facility which operated until October 2019.
The Whim Creek Project tenure consists of seven mining leases, two exploration licences and one miscellaneous licence encompassing an area of approximately 175km2 of fertile volcanic and sedimentary units of the Whim Creek Greenstone Belt and geologically contemporaneous Mallina Formation.
An Environmental Protection Notice (EPN) is current for the Whim Creek Project where groundwater contamination has been noted in regular bore monitoring around the heap leach facility infrastructure. Venturex and site operators, Blackrock, have suspended copper production, in line with EPN requirements, in order to enable investigation and management of the contamination. The clay lined environmental pond, refurbished in 2012, is the suspected source of contamination and plans are in place to clean, test and repair the pond.
Anax is working with Venturex and Blackrock to ensure compliance with all environmental regulations to mitigate damage to the environment and prevent further contamination.
Anax’s development plans in the near term are not dependent on the licencing or operation of the heap leach facility or the EPN and would be separately permitted. To this end, Anax intends to carry out a pre-feasibility programme that will include:
- Drilling of 3 to 5 diamond holes for geotechnical analysis and to obtain metallurgical samples from Mons Cupri and Salt Creek;
- Ore sorting, flotation and heap leach recovery test work;
- Geotechnical studies;
- Pit optimisation and underground development;
- Site Design;
- Environmental studies, including materials characterisation, hydrogeological investigations, surface water investigations, etc
The semi-arid climate of the west Pilbara has extremely variable annual rainfall of between 250 and 400mm, largely dependent on the formation of seasonal tropical cyclones offshore between December and April. Summer maximum temperatures reach 40˚ to 45˚, while mild winter temperatures average 25˚ by day, and 12˚ at night.
The vegetation of the West Pilbara is closely related to topography, soil type and proximity to the coast. In the Whim Creek area, broad floodplains are dominated by short grass savanna mixed with spinifex and dotted with dwarf acacia shrubs. Ephemeral streams are lined with eucalypts and the rocky hill slopes are sparsely vegetated.