お知らせ • Sep 25
Arcadia Minerals Ltd Announces Declaration of Maiden Resource at Advanced Swanson Tantalum/Lithium Exploration Project in Tantalite Valley
Arcadia Minerals Ltd. announced the declaration of a maiden resource at its advanced Swanson Tantalum/Lithium exploration project situated in Tantalite Valley, Namibia through its 80% owned Namibian subsidiary Orange River Pegmatite (Pty) Ltd. Snowden Mining Industry Consultants have delivered a JORC mineral resource estimate report to ORP styled "Report for Orange River Pegmatite (Pty) Ltd, Geology and Mineral Resources of the D and F Pegmatites, September 2021." A total of 15 Ta2O5 mineralised pegmatites have been identified in the Swanson Swarm pegmatites on the Orange River Pegmatite (Pty) Ltd. (ORP) property. The Swanson Project comprises an area of 83 ha out of a total 1010 ha are known to contain pegmatites in the license area. This Mineral Resource estimate (MRE) has quantified the outcropping and shallow resources on four of the 15 pegmatites, namely the D0, D1, D2 and F pegmatites. These pegmatites are of uniform thickness (generally about 1.5-2.5 m thick), are tabular, non-zoned, gently dipping, and contain tantalum, niobium and lithium mineralisation, together with quartz, sugary albite, spodumene and a number of other minerals. Mineralogically, the four main constituents of the pegmatites are white to grey massive quartz, crystalline perthitic feldspar, lithium muscovite, and sugary albite. Minor constituents are spodumene, beryl, lepidolite, muscovite, apatite, fluorite, biotite, tantalite and microlite. The pegmatites intruded into competent meta-gabbros and are bound on the northern side by a northwest trending mylonitic zone. The pegmatites outcrop on surface and have been mapped and sampled in outcrop and through vertically drilled shallow diamond drillholes. The pegmatites exhibit clearly defined and sharp hanging wall and footwall contacts and show very good geological continuity in outcrop, and as interpreted from surface intersections. They are uniform in thickness over large distances. Tantalum and niobium grades are uniformly distributed spatially, although there are areas of higher and lower grades. Higher lithium grades are confined to certain areas and are not associated with higher tantalum grades. An initial drilling program completed in August 2020 1 was undertaken after a detailed mapping and sampling programme was conducted by ORP over exposed outcrop, which tested several pegmatites in the Swanson pegmatite swarm. Fifteen Lithium Caesium and Tantalum (LCT) well-mineralised pegmatite bodies were identified and alpha-numerically (A1 to F1) named for ease of reference. The initial drilling program, which consisted of 23 diamond drilling holes for a total of 349.85m was conducted over three of the 15 pegmatites, namely D1, D2 and F1, of which results are shown in Annexure 12. The Mineral Resource estimate stated in this announcement has been quantified from the outcropping and shallow resources on four of the 15 pegmatites, namely the D0, D1, D2 and F pegmatites. In addition, this estimate has incorporated all geological knowledge and exploration information up to 21 September 2021. A total of 23 vertical diamond drillholes were drilled at three pegmatites. The drillholes are HQ with a 63.5 mm core. The holes were drilled with a 50 m strike spacing and 50 m on dip spacing on drill lines and have a total core length of 349.85 m. The depth of the holes ranged from 4 m to 33 m. The holes were logged, and half core sawn samples were sampled and analysed on a 1 m sample length. At the laboratory the samples were crushed to 2 mm. A 200 g subsample of the crushed material was taken to be milled in a carbon milling pot to 90% <75 micron. Samples consisted of half core, with the core being split using a saw. Approximately 200-220 g of sample was taken per drilled mineralised metre was recovered. Half core samples were also taken for comparison purposes. 0.25 g of the milled material was prepared and analysed through inductively coupled plasma-optical emission spectroscopy (ICP-OES) analysis for tantalum, niobium, and lithium. ORP added a total of 19 standards and the laboratory added an additional nine standards to the samples. A total of 22 blanks AMIS0439 (Blank Silica Chips) were added to the samples. Geological continuity of the pegmatites has been established through mapping and sampling (chip and channel) of surface exposures, and the extension of these pegmatites under shallow cover has been established by diamond drilling. The thickness of the pegmatites has been established through modelling of the hanging-wall and footwall contacts in Leapfrog software. Where bifurcation was present in the D pegmatites this was modelled. Minor northwest-southeast faults, with displacements of <2 m, were modelled. Each pegmatite was modelled separately, and as no zoning was apparent, either physically of from the chemistry, these were grade modelled as a single unit. The interpolation parameters were based on the variogram parameters. The Snowden Supervisor software was used for exploratory data analysis and for the variography. Ordinary kriging was used to estimate grades. The block size used was 10 m x 10 m x 2 m. Ta2O5 ppm, Nb2O5 ppm and Li2O% grades have been estimated using ordinary kriging, with geostatistical continuity of the Ta2O5 grades being established through variographic analysis. It was assumed that the SMU would be equivalent to the block size. As the entire pegmatites were considered to be economic, no selective mining is envisaged. The cut-off grade is based on reasonable costs, and on the recovery of tantalum alone, with recovery assumptions of 67% Ta based on metallurgical testwork. Although economic concentrations of lithium are present, these were not considered. Niobium is present in solid solution in the tantalum, and this was taken into account in the metallurgical testwork. The Mineral Resources were classified as Indicated from outcrop to the last line of surface boreholes. Up to 50 m beyond the last line of holes was classified as Inferred.