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July 25, 2007
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African Copper Plc: Independent Resource Estimate for Thakadu Copper-Silver
Project Shows Potential for New Development
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LONDON, UNITED KINGDOM--(Marketwire - July 25, 2007) - African Copper Plc (TSX:ACU)(AIM:ACU)(BSE:AFRICAN COPPER) -
- Final results have been received from RSG Global Consulting ("RSG") for a resource estimate at the Company's 100% owned Thakadu Project in Botswana.
- RSG reports an estimated indicated mineral resource of 4.715 million tonnes grading 1.72% copper and an estimated inferred mineral resource of 0.961 million tonnes at 1.29% copper. In each case, estimated mineral resources represent a mineralized envelope based on a 0.25% copper cut-off utilizing ordinary kriging.
- Contained within this estimate, is an indicated silver resource of 3.558 million tonnes grading 16 g/t silver.
- These mineral Resource Estimates are SAMREC, JORC and NI 43-101 compliant.
- Locked cycle metallurgical results show average abrasion and bond work indices for the style of mineralisation with 92% to 94% recovery producing a concentrate grading between 30% and 32% copper.
- The Company is proceeding with open pit optimisation studies with the objective of early exploitation of this resource.
African Copper Plc ("African Copper" or the "Company") is pleased to announce the results of comprehensive mineral resource estimates for the Company's Thakadu Project in Botswana completed by independent consultants RSG Global Consulting ("RSG"). These estimates include data from 7,700 metres of infill and twin hole drilling in 42 drill holes and incorporate data from 70 historic drill holes (12,200 metres).
"Thakadu has always represented the most advanced exploration property for African Copper after the Dukwe Project. The delivery of mineral resource estimates for Thakadu greatly enhances our ability to complete scoping level studies on these deposits", commented Joseph Hamilton, Chief Executive Officer of African Copper. "We are excited and encouraged by the results of our latest drilling programme both for the confidence level in our resource estimates and for the increased understanding of the geology of the area. We have prioritized a number of excellent exploration targets along strike from Thakadu and are currently drilling these in a systematic manner."
The Thakadu deposit is a broadly stratabound disseminated copper-silver deposit hosted in a deformed quartzite unit that is immediately adjacent biotite schists. Mineralisation generally occurs as chalcopyrite and bornite which has been oxidized to malachite, azurite and tenorite in the near surface portions (less than 40 metres) of the deposit. Mineralisation boundaries are sharp. Mineralisation is largely contained within the quartzite units but may locally extend into the adjacent biotite schist in areas of intense mineralisation. The quartzite unit ranges in thickness from 2 metres to over 30 metres and strikes west-northwest with a 40 degrees to 70 degrees south-southwest dip. Mineralisation seems to have a moderate plunge to the west-southwest at about 41 degrees.
RSG reports an estimated indicated mineral resource of 4.715 million tonnes grading 1.72% copper (178.7 million pounds of contained copper) and an estimated inferred mineral resource of 0.961 million tonnes grading 1.29% copper (27.37 million pounds of contained copper) (See Table 1). In each case estimated mineral resources represent a mineralized envelope based on a 0.25% copper cut-off utilizing ordinary kriging. The Company believes that the use of a 0.25% cut-off is African Copper Plc Press release 25 July 2007 Page 1 of 1 appropriate given the stratabound nature of the mineralisation and the sharp assay cut-offs that exist.
Historic drilling at Thakadu did not always include silver assays. All recent drilling included assays for silver. As a result outlying areas of the mineralisation could not be included in the volumes utilized for estimating the silver resource. Consequently the tonnage reflected in the estimate for silver resources is a subset of the copper resource estimate. RSG reports an estimated indicated mineral resource of 3.558 million tonnes grading 16 g/t silver (1.88 million ounces of contained silver).
Locked cycle metallurgical tests have been completed on samples of mineralisation from the Thakadu mineralisation. A total of 263.44 kilograms of drill core was collected across the drilled strike length of the Thakadu mineralisation and was submitted for testing. Abrasion and bond work indices show global averages for copper mineralisation. Flotation tests have shown mass pulls between 6% and 9% with 92% to 94.6% recoveries of contained copper resulting in a concentrate with a copper grade between 30% and 32.4%. All metallurgical work was completed at SGS Lakefield Research Africa (Pty) Ltd., an independent and internationally accredited laboratory facility.
African Copper is proceeding with open pit optimisation studies in preparation for exploitation studies of the Thakadu deposit. Following these studies, the Company will review the possibility of integrating Thakadu into the Dukwe mine plan, or examine stand-alone possibilities. A number of high-priority geochemical-geophysical exploration targets are currently under study in the vicinity of Thakadu. Results will be released as they become available.
Table 1: Mineral Resource Estimates for Thakadu Project (prepared by RSG Global Consulting, July 2007)
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Indicated Mineral Resource
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Copper Resource Silver Resource
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Grade Content Grade Content
Tonnage Cu(%) lbs Tonnage Ag (g/t) Troy ozs
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Oxide 1,142,000 2.44 61,461,000 1,141,000 22 825,000
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Sulphide 3,573,000 1.49 117,264,000 2,417,000 14 1,057,000
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Total 4,715,000 1.72 178,725,000 3,558,000 16 1,882,000
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Inferred Mineral Resource
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Sulphide 961,000 1.29 27,374,000
------------------------------------------------------------------------Note: RSG Global Consulting ("RSG") is an independent consulting firm commissioned by African Copper. The above RSG estimates were prepared under the supervision of Ken Lomberg, Pr. Sci. Nat.. who is an employee of RSG and a "Qualified Person" for the purposes of National Instrument 43-101 in Canada. Mr. Lomberg has reviewed and approved the contents of this press release. The estimates have been completed to SAMREC, JORC and National Instrument 43-101 definitions and standards. All sample preparation and analyses were completed at ALS Chemex laboratories in Johannesburg (ISO 17025 accredited and independent of African Copper and RSG). Copper and silver assays are completed using standard preparation of crushing to 70% less than 2 mm followed by splitting and pulverizing to 85% less than 75 micron. Analyses were generally completed utilizing 27 element four-acid ICP-AES in addition to a four-acid ore-grade element digestion followed by ICP-AES. Any over-limit analyses were reanalyzed using an ore-grade four-acid digestion with AA or ICP-AES finish. QA/QC procedures included the submission by RSG of systematic duplicates, blanks and both low-grade and high-grade standard samples within the sample batches submitted to ALS Chemex. Control samples comprise 20% of all samples submitted. Referee analysis for the dataset has been completed. The results of the QA/QC programme for copper analyses have been reviewed by RSG. RSG utilized an ordinary kriging methodology with block size of 10m x 10m x 3m and 1 m composites to complete the estimates. In addition to a number of geological criteria, indicated resources in this model are the sum of those blocks that have a minimum of 3 composite samples and a maximum of 20 composites contained with a maximum of six samples from a single drillholes and that lie within a 135 metre distance of the centre of the block estimated. In addition to a number of geological criteria, inferred resources are the sum of those blocks, not in the indicated category, that have a minimum of 1 composite sample and a maximum of 50 composite samples from a maximum of 6 samples from a single drillholes and that lie within 180 metres of the centre of the block estimated. Omni-directional variograms were utilized and major and semi-major axes of the search ellipse were rotated 45 degrees from vertical and horizontal respectively. Average oxide bulk density was 2.61 grams per cubic centimetre and average sulphide bulk density was 2.75 grams per cubic centimeter.
African Copper Plc Press release 25 July 2007 Page 2 of 2 Additional information with respect to the Thakadu Project is contained in a technical report dated March 30, 2006 and entitled "Technical Report on the Dukwe Copper Project and Matsitama Prospecting Licences, Botswana, Africa", a copy of which can be obtained under the Company's profile on SEDAR at www.sedar.com. A new National Instrument 43-101 technical report describing the property and the above resource estimates will be filed on the SEDAR website shortly.
African Copper is a tri-listed (AIM, TSX, Botswana Stock Exchange) international exploration and development company. The Company is planning to develop its first copper mine at the Dukwe Project in Botswana and commence production in 2008. The Company's other interests are the 2,000 sq km Matsitama exploration concession adjacent to Dukwe, which contains two known copper deposits and numerous base metal exploration targets. African Copper has approximately 139.6 million shares outstanding.
Mr. Joseph Hamilton, P.Geo., and Chief Executive Officer of African Copper, is a "qualified person" as defined in Canada by National Instrument 43-101. Mr. Hamilton has verified the data pertaining to the metallurgical testwork in this press release. This press release has been prepared under Mr. Hamilton's supervision.
This press release contains or refers to forward-looking information, including statements regarding the estimation of mineral resources, exploration results, potential mineralisation, exploration and mine development plans, timing of the commencement of operations and estimates of market conditions, and is based on current expectations that involve a number of business risks and uncertainties. Factors that could cause actual results to differ materially from any forward-looking statement include, but are not limited to, failure to convert estimated mineral resources to reserves, the grade and recovery of ore which is mined varying from estimates, capital and operating costs varying significantly from estimates, the preliminary nature of metallurgical test results, delays in obtaining or failures to obtain required governmental, environmental or other project approvals, political risks arising from operating in Africa, uncertainties relating to the availability and costs of financing needed in the future, changes in equity markets, inflation, changes in exchange rates, fluctuations in commodity prices, delays in the development of projects and the other risks involved in the mineral exploration and development industry. Forward-looking statements are subject to significant risks and uncertainties, and other factors that could cause actual results to differ materially from expected results. Readers should not place undue reliance on forward-looking statements. These forward-looking statements are made as of the date hereof and the Company assumes no responsibility to update them or revise them to reflect new events or circumstances other than as required by law.
The mineral resource figures for the Thakadu project disclosed in this press release are estimates and no assurances can be given that the indicated levels of copper and silver will be produced. Such estimates are expressions of judgment based on knowledge, mining experience, analysis of drilling results and industry practices. Valid estimates made at a given time may significantly change when new information becomes available. While the Company believes that the resource estimates disclosed in this press release are well established, by their nature resource estimates are imprecise and depend, to a certain extent, upon statistical inferences which may ultimately prove unreliable. If such estimates are inaccurate or are reduced in the future, this could have a material adverse impact on the Company. Mineral resources are not mineral reserves and do not have demonstrated economic viability. There is no certainty that mineral resources can be upgraded to mineral reserves through continued exploration. The Company is not aware of any environmental, permitting, legal, title, taxation, socio-political, marketing or other issue that may materially affect these estimates of mineral resources.
Further information about our properties, to download a copy of our Annual Report or any technical report or to access our Press Release Archive please visit www.sedar.com or our website at www.africancopper.com.
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