Next Phase: Lithium should be close to reporting on LCT...

Next Phase: Lithium should be close to reporting on


LCT Pegmatite Targeting

As part of a litho-geochemical study indicator elements traditionally associated with rare metal granitic pegmatite occurrences have been reviewed, using bedrock geochemistry and pXRF data (Rb only), to assess lithium and other rare metal prospectivity potential over the target areas drilled to date.

Lithium (Li), rubidium (Rb) and caesium (Cs) values were modelled to identify possible dispersion haloes around a potential pegmatite source, which can be interpreted as a distal signature, and a potential vector to an ore forming system. Some examples of lithium haloes related to Archaean LCT pegmatites in Canada may have up to kilometre scale extents (Selway et al., 2005).

Other factors used in targeting relate to favourable host rock types and structures recorded elsewhere in the Pilbara region, such as mafic or ultramafic rocks and associations with major structures (e.g., Sweetapple and Collins, 2002). Additionally, drilling has shown the presence of less magnetic granites intruding the greenstones.

This granite may be analogous to the similar ‘fertile’ granites of the Split Rock Supersuite which provide source rocks for pegmatite generation. The granites of this Supersuite are characterized by their less magnetic signature.

Target areas 2A and 5 showed the greatest abundance of the indicator elements Li-Rb-Cs which encouragingly are hosted in mafic and ultramafic units within a suitable structural framework (Figure 2). Li-Rb-Cs element assays in these target areas are considered to be elevated to highly anomalous.




Figure 3: Lithium target locations with interpreted basement units from geochemistry and regional magnetics