massive nickel copper sulphide at Mawson prospect

Legend Mining uncovers new massive nickel copper sulphide at Mawson prospect

Legend Mining Limited (ASX: LEG) has announced that more massive / semi-massive nickel-copper sulphide and mineralised intrusion were revealed from the diamond drilling at the flagship Mawson nickel-copper-cobalt prospect within the Rockford project, Fraser Range, Western Australia.

The company announced that the DD hole RKDD053 intersected 31.2m sulphide zone including 16.1m of massive and semi-massive nickel-copper sulphide, and 7.77m matrix nickel-copper sulphide. LEG reported that the DD holes RKDD046/049/051 intersected wide sulphide zones extending prospective intrusion 200m north and west of previous drilling.

The company said that the Downhole EM is ongoing, identifying multiple targets.

Diamond Drillhole Locations and defined Chonolith model projected to surface over Aeromagnetics
Aeromagnetics map showing locations of massive sulphides at the Mawson nickel-copper-cobalt prospect

Diamond drilling at Mawson prospect

The company had recently commenced diamond drilling at the flagship Mawson nickel-copper-cobalt prospect.


Legend said that the assay results from drillholes RKDD035-RKDD042 were received, returning intervals of low-grade Ni-Cu values in the range 0.05-0.2% Ni associated with disseminated sulphide in mafic/ultramafic intrusive, as expected. The company said that the results from drillholes RKDD043 and RKDD044, which intersected significant Ni-Cu sulphide intervals are expected within the next 2-3 weeks.

Next nine DD holes

LEG has now reported the results of the next nine diamond drillholes (RKDD045-RKDD053). Of these DD holes, RKDD053 was designed to test an offhole conductor from RKDD043, whilst holes RKDD045 – RKDD052 continued the systematic step-out diamond drilling across Mawson, adding critical data to existing datasets.

Encouraging DD results


The company reported that a sulphide zone of 31.2 metres was intersected in hole RKDD053, including 16.1 metres of massive and semi-massive nickel-copper sulphide and 7.77 metres of matrix nickel-copper sulphide.

The RKDD053 summary drill log of Ni-Cu mineralisation is as shown below.

LEG reported that the DD holes RKDD046, RKDD 049, and RKDD051 also intersected wide sulphide zones, extending the prospective intrusion 200 metres north and west of previous drilling.


RKDD049 intersected a 46m zone of sulphide mineralisation from 402.8m to 448.8m downhole including semi-massive and matrix sulphide between 440m to 441.9m and 447.9m to 448.8m. The mineralised intrusion remains open to the west, east, and north. LEG said that further expansion drilling is planned to follow the mineralised intrusion in the open directions.

Exploration evolving

The company said that the step-out drilling continues to define mineralised intrusion and importantly, the architecture of the Mawson intrusion. LEG said that the 3D model driving predictive exploration at Mawson continues to evolve with additional data and continues to be very accurate. This bodes well for continued selection of targets to test for the preferred host lithologies and structurally favourable positions to host massive Ni-Cu mineralisation across the Mawson intrusion.


The company said that the downhole transient electromagnetics (DHTEM) is scheduled on RKDD053 to search for further extensions to the mineralisation.

DHTEM was completed on RKDD042 and RKDD044 and identified a large offhole conductor of significant size and thickness adjacent to the interpreted MLTEM stratigraphic conductor D3. LEG said that drillholes have been designed and will be completed east of RKDD044 to better constrain this conductor before drill testing. The company said that the ongoing drilling across Mawson will focus on continued definition of these intrusive bodies and targeting of structural trap sites for massive Ni-Cu sulphide accumulation.

Updates and next steps

The company said that the diamond drilling is continuing with two diamond rigs at Mawson systematically testing across priority areas. LEG said that the DHTEM is ongoing on all completed diamond drillholes to assist follow up drilling.

Legend said that the integration of DD, RC, aircore geochemical, and geophysical datasets to evolve 3D emplacement model of Mawson, with new constrained gravity and magnetic inversions is ongoing.

We are very pleased to announce a new zone of massive/semi massive nickel copper sulphide”

Management statements

Legend Managing Director Mark Wilson said: “We are very pleased to announce a new zone of massive/semi massive nickel copper sulphide around holes 43 and 53. With ongoing downhole EM and further drilling we expect this zone will evolve over time.

Equally pleasing is that our strategy of systematic step out drilling continues to expand the 3D footprint of the mineralised intrusive and open up further prospective horizons for future planned drilling.”

Image Source:  Legend Mining Limited

Written By Jonathan Norris
Jonathan is a founder of and has been covering the resources industry since 2018. With over 17 years experience in print, broadcast and online media, Jonathan has seen first hand the transformative effect of online niche media.