AFRICAN PIONEER PLC African Pioneer Plc announced the results of an updated Indicated and Inferred Mineral Resource Estimate for the Ongombo copper project ("Ongombo" or the "Project") in Namibia, completed by independent consultants Addison Mining Services. African Pioneer holds an 85% interest in the Project. The Ongombo project is situated in Exclusive Prospecting License (EPL) 5772 in the Khomas region of the Windhoek District of Namibia, 45 km from Windhoek, the capital of Namibia.
The project area has relatively well-developed infrastructure on the farms Ongombo Ost and Ongombo West. The property is easily accessed by a tar road from Windhoek to Gobabis and then on a gravel road up to the project area. There is also a railway line from Gobabis to Walvis Bay, via Windhoek running parallel to the tarred road.
The Ongombo Project is located 15km northeast from Otjihase Mine which consists of two underground mines (Otjihase and Matchless) and an 800ktpa copper concentrator. The Ongombo project lies within the Matchless Member of the Kuiseb Formation, a conspicuous assemblage of lenses of foliated amphibolites, chlorite-amphibolite schist, talc schist and metagabbro. This belt, up to 5km wide in the Otjihase area, stretches 350km east-north-eastwards in the Southern Zone of the Damara Orogen from the Gorob - Hope area.
The deposit is generally described as a Besshi-type massive sulphide. These are described as thin sheet-like bodies of massive to well-laminated pyrite, pyrrhotite, and chalcopyrite within thinly laminated clastic sediments and mafic tuffs. At the Ongombo project mineralisation occurs in one continuous zone approximately 7 km long and 0.5 - 1 km wide.
The mineralisation zone dips consistently 15-20° northwest and plunges 5° northeast. Mineralisation is gradually thinning westward. In 2021 the Shali Group sold 85% equity in the Licence to African Pioneer PLC, African Pioneer are now managers and funders of the License, Shali Group are County Managers for African Pioneer.
In September 2021 a Scoping Study was completed by consultants Practara Pty Ltd. and was based on a Mineral Resource Estimate undertaken by consultantsRed Bush Geoservices. The Scoping study proposed mining entirely by underground mining and assumed a minimum mining height of 1.05 m with access via twin declines. Alternative mining scenarios have been considered in this Resource update. The pending renewal application for EPL 5772 which expired on 8 March 2023 is now reflected on the Namibian Mines and Energy Cadastre Map Portal and is for an additional two-year extension.
A conditional Environmental Clearance Certificate for mining activities was granted on EPL 5772 and is valid until 16 April 2026. A 20 Year Mining Licence, ML 240, was granted on 10 August 2022 and covers a portion of EPL 5772 and approximately one third of the open pit resource. An extension to the Mining Licence was submitted on 6 September 2022 to encompass the wider Resource Area.
The updated Mineral Resource Estimate has been completed by Addison Mining Services Ltd., an independent consultancy based in the United Kingdom and is reported in accordance with the JORC code 2012 edition. Resources are of Indicated and Inferred categories and include. Total Indicated Resources of 5.7 million tonnes gross at 1.1 % Cu Equivalent ("CuEq"), 0.94 % Cu, 0.23 g/t Au and 4.4 g/t Ag, for 53,000 t Cu, 42,000 oz Au and 800,000 oz Ag, including; Open pit potential Resources of 0.93 million tonnes at 0.68% CuEq, 0.57 % Cu, 0.19 g/t Au and 2.6 g/t Ag, for 5,300 t Cu, 5,700 oz Au and 78,000 oz Ag, above a cut-off grade of 0.25% CuEq; Underground potential Resources of 4.7 million tonnes at 1.2% CuEq, 1.0% Cu, 0.24 g/t Au and 4.7 g/t Ag, for 48,000 t Cu, 36,000 oz Au and 72,000 oz Ag, above a cut-off grade of 0.5% CuEq; Inferred Underground potential Resources of approximately, 23 million tonnes at 1.1% CuEq, 0.95% Cu, 0.24 g/t Au and 5.8 g/t Ag, for 220,000 t Cu, 180,000 oz Au and 4.3 million oz Ag, above a cut-off grade of 0.5% CuEq.
Immediately to the north-west of the open pit in the "central shoot" there is an estimated underground Resource inventory of 2.1 million tonnes at 1.2% Cu which maybe readily accessed by developing access from the high wall of the open pit, representing potential for a timely and efficient transition from open pit to underground mining. The remainder of the Indicated underground resource may then be accessible following further development. Further studies are required to assess the economic viability of such an operation.
Ongombo project has been explored for over 30 years and 209 historical drill holes (pre-1991) have been used to inform the estimate. The Indicated resource is restricted only to the area where new drilling (2007 and later) has been completed. The area is 2.2 km by 0.5 km.
The northwest of the Ongombo project is estimated based on historic drilling entirely (drillholes from 1991 and earlier) and is restricted to the Inferred category. The Inferred area is approximately 4 km by 0.5 km in surface expression. African Pioneer plans to explore this area following evaluation of the Indicated open pit and underground resources and, given favourable results, undertake further exploration drilling.
The Mineral Resource Estimate is based on wireframe restricted block modelling with grade estimation by ordinary kriging. Pit optimisation was used to identify material which may be amenable to open pit mining. These data are presented in Table 1 below above a cut-off grade of 0.25% CuEq, in addition to Resources that may be amenable to underground mining techniques above a cut-off grade of 0.5% CuEq.
Cu, Au and Ag grades have been diluted to reflect minimum mining width of 1.6 m. The estimate incorporates new drilling by African Pioneer completedbetween 22nd April and 15November 2022. African Pioneerdrilled 54 shallow diamond holes, totaling of 2,288.80 m (ranging between 5.89 m and 200.93 m in depth). Drillhole size was PQ in overburden with HQ tails.
All holes were drilled with inclination -75°and 142°azimuth. In addition, six drillholes completed in 2017 by Shali Group and 26 drillholes completed in 2008 and 2014 by Namibian Copper Organisation ("NCO") along with 209 drillholes completed by Tsumeb Corporation Ltd. in 1988 - 1991 were used in the estimate.
