• Field observations and historical drill logs have confirmed the presence of pegmatites in RAB drill spoil
  • Mt Malcolm Mines says the regional geological setting strongly supports the prospectivity at the Lake Johnston project
  • Assays submitted to Intertek Minerals for analysis of collected drill spoil


Special Report: Re-logging of collected spoil samples indicates more extensive pegmatite occurrences than originally documented in WA’s emerging lithium hotspot.

It was just last month that Mt Malcolm Mines (ASX:M2M) expanded its footprint in the Lake Johnston area where recent exploration success by TG Metals (ASX:TG6) has sparked a pegging rush.

TG6 reported grades of up to 2.28% Li2O from its first holes into the Burmeister prospect.

Within the same neck of the woods is Charger Metals (ASX:CHR) which recently inked a lucrative farm-in agreement with Rio Tinto’s (ASX:RIO) exploration arm following three rock chip assays from a newly discovered pegmatite at CHR’s Lake Johnston lithium project.

But field observations and historical drill logs have confirmed there’s a new contender on the scene, with the pegmatites identified in RAB drill spoil at M2M’s own Lake Johnston project.


Sampling of historical drill holes

M2M says the sampling of historical drill holes during the recent reconnaissance visit to the tenement area visually confirms pegmatites in old drill spoil, with a further five drill holes having pegmatite logged, extending known pegmatite in drilling to the central west portion of the drilled area.

Field observations have also confirmed a maximum width of around 10m of pegmatite in both drill holes LJRB009 and LJRB030.

Past exploration (1981-2016) focused on gold and nickel mineralisation, with no analysis for lithium conducted.

As the geological models depict, M2M says late stage fractionated LCT bearing fluids move out of the granitoid terrane and into the surrounding host rocks along pre-existing structural pathways and weaknesses (faults, fractures, and foliation) to form LCT pegmatite swarms.

These pegmatite swarms consist of tabular or lensoid dykes and sills in the strongly deformed Lake Johnston greenstones.


What’s next?

Examination of sampled drill spoil under fluorescence ultraviolet light (UV) confirmed salmon orange and bluish-purple, fluorescent minerals in some of the pegmatite samples.

There is a likelihood these are spodumene or lepidolite related but confirmation of the presence of lithium in these RAB hole samples – and grade – can only be confirmed upon receipt of the assay results, M2M says.

Assay results are expected to be finalised by mid-January 2024, followed by analysis of the collected drill spoil for a comprehensive lithium-related suite.



This article was developed in collaboration with Mt Malcolm Mines, 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.