The Etango Project is owned by Bannerman Energy Ltd, through its 95%-owned subsidiary Bannerman Mining Resources (Namibia) (Pty) Ltd. The other 5% is owned by the One Economy Foundation, a not-forprofit Namibian organisation.
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Summary:
Uranium mineralisation at the Etango Project is predominantly hosted by a stacked sequence of leucogranitic bodies (generally referred to as alaskite) that have intruded the host Damara Sequence of metasedimentary rocks on the western flank of the Palmenhorst Dome. The main mineralised bodies are associated with the Khan Formation and the lower part of the Chuos Formation but also occur within 400 metres of the contact between the Etusis and Khan Formations (Mouillac et al., 1986). Uranium mineralisation at Etango is defined within an approximately +5km long zone trending southeast to northeast that dips moderately (30° to 50°) to the west. The dominant primary uranium mineral at Etango is uraninite (UO2), with minor primary uranothorite ((Th,U)SiO4) as well as some uranium in solid solution in thorite (ThO2). Minor uranium is also present in the minerals monazite, xenotime and zircon, either as minute inclusions or crystal lattice substitution. Secondary uranium-bearing minerals observed include coffinite and betauraniphane (both uranium silicate minerals). Approximately 90% of logged mineralised intervals (>50 ppm U3O8) at the Etango Project occur within alaskite (Alaskite Dominant (AD); however, not all of the alaskite is mineralised, with only about 60% mineralised in total. Minor uranium mineralisation is also found in the metasedimentary sequences (Alaskite Sub-Dominant (ASD)) close to the alaskite contacts, almost certainly from metasomatic alteration and in minor thin alaskite stringers within the metasediments.
The alaskite bodies have intruded into the metasediments of the Nosib and Swakop Groups of the Damara Supergroup. These metasediments and alaskite intrusions flank the Palmenhorst Dome which is cored by Mesoproterozoic (1.7 2.0 Ga) gneisses, intrusive rocks and meta-sediments of the Abbabis Metamorphic Complex.
Uranium mineralisation in the Etango-8 Project area occurs almost exclusively in the alaskite intrusives. Minor uranium mineralisation is also found in the metasedimentary sequences close to the alaskite contacts, probably from metasomatic alteration and in minor thin alaskite stringers within the metasediments.
The dominant primary uranium mineral is uraninite (UO2), with minor primary uranothorite ((Th,U)SiO4) and some uranium in solid solution in thorite (ThO2). The uraninite is commonly associated with chloritised biotite in the alaskites and with ilmenite and magnetite within foliated alaskites. The primary uranium mineralisation occurs as microscopic disseminations throughout the alaskite, at crystal interfaces, and as inclusion within other minerals. Secondary uranium minerals such as coffinite (U(SiO4)(OH)4) and betauranophane (Ca(UO2)2(SiO3OH)2 5H2O) occur as replacements of the primary minerals or as coatings along fractures.
QEMSCAN analysis indicates that about 81% of the uranium present is in primary uraninite, while 13% is in secondary coffinite and 5% is in secondary betauranophane (Freemantle, 2009). The remaining 1% of the uranium occurs in various minor phases including brannerite, betafite and thorite. Very minor amounts of uranium are also present in solid solution in monazite, xenotime and zircon. A very minor amount of primary betafite (Ca,U)2(Ti,Nb,Ta)2O6(OH) is also present.
The Etango Project Mineral Resource area has dimensions of 7,000 m (north) by 4,200 m (east) and 500 m (elevation). It primarily includes the Etango deposit, as well as the smaller Hyena and Ondjamba deposits.