Location of Phase 1 drilling and other exploration activities Umba South is located near the junction of the Umba and
Details about exploration activities
Exploration at Umba South targeted a high grade metamorphic sequence within the Mozambique Belt that comprises paragneiss (quartzo feldspathic gneiss) and sillimanite kyanite( garnet) schists. The sequence includes accessory minerals pyrite, rutile, magnetite and graphite, with rutile the primary exploration target. The focus of exploration is secondary rutile mineralisation associated with alluvial and colluvial deposits eroding from the outcropping linear ridges of pyritic quartz feldspar gneiss, and primary rutile mineralisation within the weathered saprolite material flanking the ridge feature that is sufficiently weathered to represent free dig material from which rutile can be readily liberated. In early 2022, mechanised auger sampling of the soil profile to approximately 1m depth on a 500m x 500m sample grid was undertaken across the broader tenement area, with the best results (up to 5% rutile) reported from the flanks of Kigwase Hill. In the June quarter of 2022, rockchip sampling of the outcropping ridge confirmed the presence of rutile mineralisation, with grades of up to 2.5% rutile reported from banded gneiss on Kigwase Hill. Selected rockchip samples were sent for mineralogical analysis, and this confirmed the presence of rutile together with pyrite (in fresh samples), Fe oxides (in weathered samples), magnetite and altered ilmenite. A series of test pits were then completed to assess the soil profile, including the nature of contact with the underlying saprolite. Mapping suggests that red brown soil is typically developed within rubbly colluvium overlying the brown saprolite material. Pit depths ranged from 1.5m to 6.5m and samples of material collected from the test pits were processed at the Kwale Operations laboratory. Encouraging results were obtained from several samples with potential HM products of rutile, leucoxene, altered ilmenite and magnetite generated using conventional mineral sands processing techniques. One of the test pits, pit 11, was investigated in detail and reported in situ grades of approximately 1% rutile, 1% leucoxene altered ilmenite and 1% magnetite. Following the encouraging results from the reconnaissance exploration, the Phase 1 program was planned to obtain preliminary data regarding the sub surface geology and rutile mineralisation in the vicinity of Kigwase Hill. A 400m North South x 200m
Results from Phase 1 drilling
The sample analysis for rutile has been completed on the sand fraction using conventional mineral sands techniques (and back calculated for in situ grades). There is the potential that rutile assaysreported may not reflect true in situ grade and/or represent rutile that is readily amenable to conventional mineral sands processing. Analysis of selected oversize fractions confirmed significant rutile is present in the oversize. For holes TN092 to TN122, the oversize fraction from the first stage of sample processing was crushed and added to the sand fraction prior to HM analysis - such that these holes report a 'total' rutile grade (assuming no loss to the slimes fraction), whereas holes TN001 to TN091 report only the rutile from the sand fraction and may therefore only be a 'partial' rutile grade.
Drill logging has identified three primary geological domains, as follows: Red brown soil and colluvium with abundant gravel - typically 1 2m thick on the eastern flank of Kigwase Hill and 2 4m thick on
the western flank of Kigwase Hill. Consistently mineralised and reports high levels of ferruginous HM and significant TiO2 in the magnetic fraction. The HM is enriched in the upper part of the profile. This domain is confirmed as a viable exploration target for the province, but lacks the depth/thickness at Umba South to have significant economic potential. Brown saprolite and saprock - weathered bedrock, subdivided into sandy and clayey units. It is thought that this reflects the
protolith (quartz rich vs feldspar rich), rather than weathering intensity as there is limited evidence for a well developed chemical weathering profile with remobilisation and volume reduction. Depth of weathering ranges down to 50m but istypically 30m distal to the ridge, and localised variability is evident. The HM content is highly variable, and often variable HM magnetic fractions both down and between holes. The saprolite is considered a viable exploration target for the province, but at Umba South it appears to lack the consistent intense weathering that concentrates rutile in the upper profile and promotes free dig mining and simple processin
Grey bedrock - fresh gneiss, typically with abundant pyrite. Garnet gneiss logged distal to the ridge, but logging has not attempted to classify the bedrock lithology in detail. The HM content is variable but typically high grade (20% HM) although dominated by pyrite. The bedrock is not considered a viable exploration target for rutile due to cost and complexity that would be introduced by hard rock mining and comminution, and the negative impact of pyrite mineralisation on mineral processing recoveries and tails storage - with results only reported for geological interest.
Competent Person's Statement
The information in this announcement that relatesto the Umba South exploration resultsis based on, and fairly represents, information and supporting documentation prepared by Mr. Ian Reudavey. Mr. Reudavey is a member of the
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