logo-loader

Thundelarra finds native copper grains from drill chips from Frank Hill, WA

Last updated: 14:24 19 Mar 2014 AEDT, First published: 15:24 19 Mar 2014 AEDT

four_project_regions_358_53291c618b1c1

Thundelarra (ASX:THX) has found visual grains of native copper in drill chips encountered in drilling at the Azura Prospect, Frank Hill Project in the east Kimberley in Western Australia.

Azura is a copper prospect within the Frank Hill project area.

The grains of native copper were observed in drill chips of fresh mafic rocks.

It is consistent with the previous discovery of native copper samples at surface, but is unusual because of the nature of this copper occurrence.

Location

Sophie Downs is approximately 50km to the north-east of Halls Creek in the East Kimberley region on Thundelarra’s 100%-owned exploration license EL 80/3673.

Frank Hill is located a further 100km or so to the north-east of Sophie Downs on Thundelarra’s 100%-owned exploration license EL 80/2878. 

More detail

The program comprised four Reverse Circulation drillholes for a total of 534 metres.

Drilling was conducted over five days and intersected a sequence of fine grained mafic-ultramafic rocks.

All samples were analysed for a range of elements using a portable (hand-held) Olympus Innov-X Delta XRF analyser.  Those with XRF base metals analyses deemed anomalous or which were otherwise of geological interest were then sent for assay analysis for Au, Cu, Pb, Zn, As, Ag, Bi, Sn, W, U and Mo.

Hole TAZRC001

This hole was not assayed for these additional elements due to the presence of grains of the native copper and very fine (<1mm) quartz veinlets with inter-grown native copper that were intersected between 18 metres and 170 metres down hole.

It is suggested that the IP chargeability anomaly in this area could be caused by the native copper-chalcocite, but the disseminated magnetite in doleritic rocks could also explain the anomaly.

In summary

A gravity separation of the metallic copper grains is possible in order to better estimate total copper content and better able to identify potential targets within the area.

Conclusion

The native copper mineralisation observed and recorded from fresh mafic rocks at depth in Hole TAZRC001 is unusual and requires follow-up. 

Usual copper sample assay techniques were found to be unable to deliver a repeatable value for copper contents in the samples tested, suggesting a need for a larger sample to be submitted for gravity separation and/or screening in order to deliver a more representative copper grade with a more acceptable level of confidence.

Obtaining such a sample requires a new drill program, the details of which are yet to be planned by Thundelarra.

 

Proactive Investors Australia is the market leader in producing news, articles and research reports on ASX “Small and Mid-cap” stocks with distribution in Australia, UK, North America and Hong Kong / China

OzAurum to start drilling at Boca Rica Lithium Project

OzAurum Resources Ltd (ASX:OZM) CEO and managing director Andrew Pumphrey sits down with Proactive’s Jonathan Jackson to discuss an upcoming drilling program at Boca Rica Lithium Project in Brazil, following the identification of a spodumene zone. The company plans to start drilling in the next...

4 hours, 34 minutes ago