‘South-East’ Area Mineralization
From SRSR NI technical report:
The ‘South-East” Area is located approximately 1.5 km due east of Nemegosenda Lake, from a point half way along the lake (Figure 4). It was explored by Dominion Gulf, but there was not enough work done to define grade or tonnage. The East-Zone comprises fine-grained, massive and foliated pyroxenites, fragmental pyroxenites, garnet and wollastonite pyroxenites, feldspar-porphyritic pyroxenites and mafic syenites (all referred to by previous workers as pyroxenitic fenites and intermediate fenites), true fenites and minor calcite carbonatite, ankeritic carbonatite, carbonatite matrix breccia, pulaskite and feldspar-porphyry syenitic dykes. Magnetite-pyrochlore-rich and apatite-rich horizons are locally present within the pyroxenites. These are interpreted as original igneous compositional layering features. Apatite-biotite alteration zones (‘jacupirangites’), associated with extremely high radioactivity (>15,000 cps), are also locally present. Rock units within the area are steep to moderately west dipping, as is evident from trenching and interpreted from drill sections, (Parsons 1957).
Niobium mineralization (>0.50% Nb2O5) is common and, although generally sporadically distributed throughout this area, some significant zones were intersected. Niobium enrichment occurs in various types of pyroxenites and pegmatitic fenites. Pyrochlore is apparently the main Niobium-bearing mineral species present and is often (but not ubiquitously) associated with magnetite. Commonly, Niobium-rich rocks are anomalously radioactive. Extremely high-grade mineralization, Nb2O5 >2.5%, has been encountered locally, associated with biotite-apatite ‘jacupirangites’.
Yttrium (to 0.13%) and anomalous rare-earth element concentrations are present in garnetiferous pyroxenites, fragmental garnetiferous pyroxenites and wollastonite pyroxenites. In some cases garnet and magnetite-rich fragmental pyroxenites contain appreciable Niobium, yttrium and rare-earths. High rare-earth element concentrations (>2%) are also locally present in carbonatites, where a rare-earth fluorocarbonate mineral, possibly bastnaesite, has been tentatively identified. Another rare-earth mineral, cerianite, has been reported by previous workers.
