Aspiring Pilbara battery metals producer GreenTech is focusing on a number of juicy targets that have emerged at its Whundo copper-zinc project as it seeks to build resources to the critical mass needed to restart the operation.

Whundo, which was last mined in 2007, has an existing JORC 2012 resource of 3.6Mt at 1.2% Cu and 1.4% Zn for 93,000t of contained metal spread across two deposits – Whundo itself and Ayshia to the northwest.

But there are several reasons why GreenTech Metals (ASX: GRE) believes the surface has only been scratched when it comes to testing the full potential of the 9.2km2 project area.

Approximately 90% of drilling completed at Whundo to date has focused on the east and west lobes of the Whundo deposit, where mining has previously taken place and where over half of the total project resources are located. The rest of the tenement with the exception of Ayshia can be considered underexplored or unexplored.

Whundo and Ayshia are volcanogenic massive sulphide (VMS) style deposits, which typically occur in clusters. With several prospects already known in the project area, it appears that Whundo is no exception and   as such, there is a good chance there are more to be found.

This likelihood appears to be supported by the number of compelling targets that have been worked up by GreenTech in the months since its ASX listing at the start of the year using a combination of downhole electromagnetics, magnetics and gravity surveying.

Arguably the most compelling and highest priority is the newly identified Austin target, which showed up as a large, highly conductive (10,000+ siemens) “off-hole” EM response in a downhole EM survey conducted after recent drilling.

Austin has been modelled at over 200m strike and up to 60m down dip and potentially represents a large, deeper repeat or extension of the Whundo mineralisation.

The target has never been tested as peripheral drill holes have either been on the wrong inclination or haven’t extended deep enough.

But some of those drill holes have reported copper mineralisation at similar depths, and the target plunge is consistent with Whundo mineralisation, both of which are highly encouraging.

The known copper-zinc deposits at Whundo are associated with a cluster of adjoining magnetic anomalies, which is compelling evidence of the general association of mineralisation with high magnetic susceptibility.

The best is yet to come

Further north at the Shelby prospect, there is a deep fixed loop EM anomaly that has coincident gravity and magnetic anomalies associated with it.

The EM anomaly was tested in 2007 with a drill hole that returned 11.25m at 1.6% Cu from 391.25m, but this hole appears not to have tested the centre of the target as defined by more recent gravity and magnetic survey data.

GreenTech intends to have another go at testing the target and will look to use downhole EM to identify any accumulations of massive sulphide mineralisation.

Executive director Tom Reddicliffe said: “We are still in the early days of properly assessing Whundo and its associated deposits but with the benefit of modern exploration technology we are firmly of the view that we are yet to test the best targets.

“If we can find one or more new deposits or extensions to known mineralisation, we will be well on our way to returning Whundo to production.”

Theoretically, GreenTech doesn’t need to deliver a massive increase in resources at Whundo to start examining production scenarios.

The Radio Hill plant just 12.5km away presents an obvious processing option and the fact that it is owned by the company’s largest shareholder, Artemis Resources, is an added bonus.

Avoiding the big upfront capital outlay for a new plant would help to improve the economics of any proposed development, no matter how modest.

But the string of targets lined up is reason to be optimistic that GreenTech can produce resource growth of a significant scale.




This article was developed in collaboration with Greentech Metals, a Stockhead advertiser at the time of publishing.


This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.