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MINERAL RESOURCES OF NOVEMBER 2010 / No. 1 MINERAL RESOURCES OF INFORMATION ON THE MINING POTENTIAL OF ETHIOPIA TANTALUM KEY MINERAL FOR GADGETS AND ELECTRONIC EQUIPMENT t a Shendi Mits’iwa s H O K E Talo Ta Talo y e re Mark’os Mark ark’o a Debre Girshit’ A e Dese i Abeba Addis w A Naz A Nazret K a Koma Gore Mi’eso as h A ’ Nek’emte Dembi Dolo Biye K’obe H M A R M Waka be Abera m o a Kara e elle Qoryooleyy abe Baardheere Ju Wajir h iS Marsabit eb Balcad Afgooye Lodwar Chalbi Desert Jawhar Uarsciek Uarsciek Muqdisho (Mogadishu) Marka bb Baraawe a Lak Elgon on Kitale Afmadow Eldoret Nanyuki Nyeri Nairobi I N D I A N O C E A N Jilib lib G iamame Giamame Ta n a Mt M t. Ke t. K ny ya a Mt. Kenya m Embu Eyl W Baydhabo Moyale Gulu Ras Xaafuun Xaafuun Bender Beyla Hobyo Buulobarde Luuq Nimule Qardho Burao Beled Weyne Xuddur e D al Y o Yabelo Hurdiyo ra El K’oran E Hamer Koke awa an egel Negele Burji Caseyr e Qandala Ceerigaabo K’elafo G G Gidole Caluula O g a d e n N O E Laascaanood A Maji D The Brothers Degeh Bur NS MT BO ir Ginir D E Goba AU Wa EN D bi M O Sh Batu Megalo B Ba ebe R e irga Alem l s Hosa’ina A Abd-Al-Kuri Abd-AlAl Ku Kuri ri Bender Qaasim Shiikh Hargeysa Asela G i l o Socotra Socottr S tra N Berbera Bullaxaar Dire Dawa S H Harer TN F Gulf of T Tadjou Tadjoura adjou dj ra Karin Saylac S Abuye A buye ye Meda y Birh Debre Birhan Ankober Kisumu Introduction Mot’a ot a O L F G U T Debre Tabor Alefa A C Aba N U B I A N D E S E R T Aseb Ase As Sek’ot’a Dabat P L AT E A U G e Gonder Lalibela i Dangila Irqah Ahwar ETHIOPIAN Gallab abat Gallabat Dunkur Lawdar Shaqra Mek’ele M Melau Ash Shihr Yarim Yarim im Zabid Ed Adigrat Adwa Setit Singa Er Roseiress Adi K’eyah Al Mukalla Dhamar Al Hudaydah h as Gedaref ra Asmera Adi Ugri w Om m Hajer je Wad Medánî ed Renkk Sebderat Kassala s Ga Abu Gamel Abay Omdurmân Khartoum K Kosti San‘a Keren ra Tantalum is a strategic metal being a key metal in one of the most used gadgets in modern society, the mobile phone. Tantalum is also used in other types of electronic equipments and is thus high in demand. The trade name for the most common tantalum-bearing mineral is coltan whereas the mineralogical name is columbite. Ethiopia presently supplies close to ten percent of the World production of tantalum and has a good potential for a considerable expansion of the percentage. R b MINERAL RESOURCES OF Tantalum in Ethiopia Kismaayo Garissa Buur Gaabo Kitui Kajiado Ethiopia is located on the horn of africa bordering The Kenticha tantalum- Sudan, Somalia, Kenya and Eritrea.. bearing pegmatites were first discovered during a 1:250.000 scale geological intruded by a number of pegmatites mapping programme carried among which the Kenticha pegmatite out by Ethiopian geologists in field stand out. close cooperation with Soviet geologists in 1980. A major mapping The Kenticha pegmatite field and evaluation programme financed by Pegmatites are abundant throughout the Soviet Union was carried out in 1981 ultramafic volcanic rocks and metasedi- the southern part of neoproterozoic to 1985. The project aimed at determin- ments. After several phases of deforma- rocks, but are especially abundant in the ing the extent of the tantalum-bearing tion and metamorphism the units were Kenticha pegmatite field area where rocks and to establish whether they were of commercial interest. The Kenticha pegmatite is situated in the Adole area within the Precambrian basement of southern Ethiopia, which is the southern part of the Arabian-Nubian Shield formed by accretion of ocean arc terranes. The Neoproterozoic rocks can be divided into two distinct lithologic units: 1. Granite-gneiss complex and 2. Ophiolitic fold and thrust belts. The latter are composed of mafic and 2 Table they occur in an area of about 2,500 km2. Lake Tana The pegmatites are emplaced at or near a major NNE-SSW trending shear zone. The pegmatites range from barren feldspar-muscovite pegmatites to differ- Addis Ababa ent types of rare-element pegmatites. Geology: Modified from Mengesha et al.(1996) Geological map of Ethiopia, second edition, 1:2,000,000 pegmatite exposed for 2 km in length and 400 to 700m in width. It was emplaced in package of steeply dipping serpentinites and talc-tremolite schists. The thickness of the pegmatite varies. In locations where both hanging and foot wall contacts are exposed, thickness ranges between 40 and 100m. High-grade Precambrian Undifferentiated gneisses and schists The Kenticha pegmatites display Low-grade Precambrian complex zoning with up to nine mineral Metaultramafic-mafics paragenetic assemblages. Apart from columbite a number of lithium minerals, beryls and sulphides are found. Precambrian Phanerozoic Intrusives Metavolcano-sediments Gabbro Diorite Granite-tonalite Paleozoic Rocks Sandstone and tillites Mesozoic Rocks Undifferentiated sediments Cenozoic Rocks Early-Mid Tertiary basalt Upper Tertiary-Quaternary basalt Mid Tertiary-Quaternary felsic rocks Early Tertiary sediment Upper Tertiary-Quaternary sediment Fig. 1. Simplified geological map of Ethiopia with localities of building stone in the central and southern parts of the country. Tantalum deposit The Kenticha tantalum deposit is mined coltan. by Ethiopian Mineral Development In the Kenticha pegmatite certain Share Company (EMDSC). The produc- parts of the coltan mineralization does tion is around 70 tonnes of Ta metal per carry low levels of uranium. Uranium in year (120 tonnes of concentrate at 60 coltan can be a problem or an asset percent Ta2O5. The probable reserve of depending on the level of uranium. In primary ore is 17,000 tonnes at Ta2O5 at most parts of the Kenticha coltan the a grade of 0.017 percent Ta2O5, whereas uranium is below the critical level of the reserve of Ta2O5 in the weathered 0.5%. Certain markets e.g. Europe does zone was calculated to 2400 tonnes at 0.015 percent Ta2O5. Additional commodities The pegmatites in the Adola area display a variety of minerals of which the lithium bearing phases such as spodumene and Li-micas over time may be a valuable additional by-product. Coltan is known to host a number of element such as rare earth elements (REE) of which neodymium (used for powerful magnets) europium used in TV screens are the best known. Uranium is also a frequent element hosted in Kenticha mine 3 MINERAL RESOURCES OF The Kenticha pegmatite is a large Ministry of Mines and Energy of Ethiopia Dear Investor MINERAL RESOURCES OF We take this opportunity to welcome you to Ethiopia We promise to make every possible effort to provide you all required information on the mineral sector in Ethiopia If you require information on the mining law, licensing conditions and the investment climate in Ethiopia Please contact the Mineral Licensing and Administration Core Processes: Ministry of Mines and Energy Outcrop of tantalum pegmatite Mineral Licensing and Administration Core Processes P.O.Box 486 not allow import of coltan with uranium con- Addis Ababa, Ethiopia tents above 0.5% whereas other markets e.g. Tel. +251 11 6461214 China allows higher uranium contents. Fax +251 11 6463454 Presently the Ethiopian Mineral Development Share Company seeks partners to devel- Columbite crystals in pegmatite op a plant to separate uranium from the tanta- Email: www. lum. zone hosting the Kenticha rare metal peg- Further potential No systematic exploration has been carried matite can be followed for more that a hundred kilometres towards North containing a number of columbite showings. out for further rare metal pegmatites. Reports of columbite minerals in placer However, in the surrounding a large number of deposits further north towards the border to small showings of coltan have been found, Somaliland, and the presence of several coltan many of which are mined by small-scale min- mineralizations across the border near ers. These are only surface deposits. Hergiesa substantiate the assumption that However, information from the company mining the pegmatite indicate that the shear there is a vast potential for finding further commercial tantalum deposits in Ethiopia. If you require information on the geology and mineral opportunities in Ethiopia Please contact The Geological Survey of Ethiopia (GSE): Geological Survey of Ethiopia P.O.Box 2303 Addis Ababa, Ethiopia Tel. +251 6 464482 Fax +251 6 463326 Email: [email protected] www.geology.gov.et Weathered out columbite crystals 4 We are looking forward to your mining investment in Ethiopia