Lithium Exploration & Development
LCT complex pegmatites develop above and adjacent to fractionated granites where favourable pegmatite chemistry has caused significant enrichment of elements such as Sn,Ta and Li. A concealed ridge of granite has been proposed (Whitelawet al., 1915) between the Mt Wills Granite and the Yabba Granite (Dorchap DykeSwarm – see Map above), acting as a potential source of Li, Sn and Ta in the dykes of the belt. Limited work by the Geological Survey of Victoria(Maher & Morand, 2003) suggests the dyke chemistry indicates an exotic source for the mineralised pegmatites from a concealed granite source rock. Limited assay data of tin mineralised dykes in the Mitta Mitta area from this work shows elevated Li, Ta, Cs and Rb consistent with the LCT Pegmatite class. The Glen Wills tin field was discovered in 1887 and the Eskdale – Mitta Mitta field followed in 1891 but both were abandoned following the discovery of gold in the same areas by 1895. A brief revival of tin prospecting in the dykes occurred in 1911 defining 100 mineralised pegmatites near Mitta. The Geological Survey of Victoria mapped a total of 1480dykes and 73 reefs (Whitelaw et al., 1915) with an additional 367 dykes and 36reefs mapped by Cuffley (1978) in the Eskdale – Mitta area which were outside the area of the Whitelaw et al., (1915) mapping. Regardless of thesource, the belt has been described as “virtually saturated with pegmatite dykes” – (Essex Minerals, 1978), the recent confirmation of lithium mineralisation supports the proposed exploration in this newly recognised region that remains unexplored for lithium.