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Tuesday, 02/21/2006 7:07:42 AM

Tuesday, February 21, 2006 7:07:42 AM

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African Copper Plc: Locked Cycle Flotation Results Improve Recoveries at Dukwe

LONDON, UNITED KINGDOM--(CCNMatthews - Feb. 21, 2006) - African Copper Plc (TSX:ACU)(AIM:ACU)(BSE:African Copper) -

- Locked cycle flotation results have confirmed the amenability of oxide, supergene and sulphide ore to recovery within a standard flotation concentrator.

- Sulphide recoveries of 92% have been achieved at a coarse grind size of -150 microns producing a marketable concentrate that grades approximately 34% copper, 30% iron and 32% sulphur.

- Supergene recoveries have improved from previous tests with 86% recovery from a -150 microns grind. A combined oxide-supergene concentrate can be produced which grades approximately 30% copper, 14% iron and 11% sulphur.

- Preliminary Heavy Media Separation of run-of-mine sulphide material has shown a promising 84% recovery of copper-bearing minerals with a 7.5% mass pull. This result may have positive implications for lowering underground mining costs at the Dukwe Project through the utilization of bulk mining techniques of the primary sulphide zones.

- Milling characteristics show average work indices - standard crusher/ball mill configurations are suitable for grinding.

-The flowsheet for a concentrator has been finalized with 3-stage crushing followed by grinding and a two-stage floatation.

African Copper Plc ("African Copper" or the "Company") announces the following metallurgical results from the locked-cycle phase of testing on material from the Dukwe Project in northeastern Botswana. These tests were completed at SGS Lakefield Labs in Johannesburg and supervised by Senet CC, both independent of African Copper. These latest tests were designed to check the amenability of copper recovery to standard flotation techniques. On the basis of these results, African Copper has finalized the flowsheet for the flotation concentrator at the project.

Capital and operating costs for the concentrator option were released previously (see Press Release dated 10 January 2006). Permitting has commenced for the Dukwe Project, construction of the access road is underway, and the Company has secured secondary and tertiary crushers.

"These results improve upon the open-cycle tests by improving the copper recovery and increasing the grade of the concentrates. The concentrates are clean and of marketable quality. We expect to finalize off-take agreements shortly", commented David Jones, CEO of African Copper. "We are finalizing underground mine plans for the extraction of near-surface supergene material and the subsequent treatment through a concentrator. Supergene material is higher grade than the deeper primary sulphide mineralization and its early extraction should enhance the economics for Dukwe. "

Bench scale flotation and locked-cycle test results have demonstrated the amenability of supergene and sulphide ores to recovery within a flotation concentrator designed to recover both sulphide and oxide copper minerals. The material can be delivered to the mill as a combined feed with both oxide and sulphide mineralization treated together through sequential flotation. These results have been used as the basis for the process selection and forecast recoveries for the Dukwe Concentrator.

Grinding tests have shown that the supergene and sulphide material at Dukwe is of average grinding characteristics. Abrasion and Work Indices are shown in the table below:



----------------------------------------------------------------- Industry Average (as per SME Mineral Sulphides Supergene Processing Primary Handbook)-----------------------------------------------------------------Bond Abrasion Index 0.67 0.50 0.50-----------------------------------------------------------------Bond Ball Index 14.5 14.8 14.1-----------------------------------------------------------------Rod Mill Work Index 13.0 13.1 15.8-----------------------------------------------------------------




The individual recoveries of each type of feed are shown below. In the supergene tests, the selective leaching of the composite sample showed 26% oxide copper. The amount of oxide copper in the weathering profile decreases with depth, and this composite is believed by the Company to represent the average mill-feed over the first three years of planned mining. These tests were conducted using a -150 microns grind size. Further test work is underway to determine whether the grades of the oxide concentrate can be improved.



--------------------------------------------------------------------- Weight Assays, % Recovery, % ----------------------------------------------- % Cu Fe S Cu Fe S -----------------------------------------------Sulphide Composite Cu Concentrate 4.3 33.7 30.3 32.3 91.9 43.8 53.5------------------------------------------------------------------------------------------------------------------------------------------
Supergene Composite Sulphide Cu Concentrate 3.7 42.3 11.4 13.2 63.1 10.7 60.8 Oxide Cu Concentrate 3.4 17.2 15.8 8.5 23.2 13.5 35.6 ----------------------------------------------- Combined Cu Concentrate 7.1 30.4 13.5 11.0 86.3 24.2 96.4---------------------------------------------------------------------




Multi-element analyses conducted on the three types of concentrates indicate that all concentrates fall within acceptable smelter impurity limits for sales to a smelter.

Heavy liquid separation tests using a media with a specific gravity of 2.96 returned encouraging results. The coarse grained nature of the Dukwe mineralization results in very few fines produced during crushing and little copper is lost to slimes in this process.

The gangue minerals are essentially quartz, carbonate and graphite which readily float while the copper bearing minerals are essentially chalcopyrite and chalcocite which readily report to the heavy fraction. Preliminary testing on a crush size of 90% passing 1.7mm resulted in about an 84% recovery of copper to the heavies with a 7.5% mass pull from a sample of sulphide material that graded 1.47% copper. This result has positive implications for bulk mining of the deeper sulphide zones since a Dense Media Separation plant between the crusher and mill may provide a quick, inexpensive pre-concentration step. Bulk mining of the sulphide zones may result in lower mining costs, lower development capital and a reduced mining risk. Further Dense Media Separation studies are planned for the sulphide mineralization although initial underground mining of the supergene material will be treated through conventional flotation.

African Copper is a tri-listed (AIM, TSX, Botswana Stock Exchange) international exploration company. In addition to the Dukwe Project, the Company's other interests are the 4,000 sq km Matsitama exploration concession adjacent to Dukwe, which contains two known copper deposits and numerous base metal exploration targets. A technical report on the Dukwe Project and the Matsitama concession dated 5 May 2005 and entitled "Technical Report on the Dukwe Copper Project and Matsitama Prospecting Licences Botswana, Africa" can be found on SEDAR at www.sedar.com. African Copper has approximately 52 million shares outstanding.

Mr. Joseph Hamilton, P.Geo., and Chief Operating Officer of African Copper, is a "qualified person" as defined in Canada by National Instrument 43-101. This press release has been prepared under Mr. Hamilton's supervision. Mr. Hamilton has verified the data disclosed in this press release including the sampling, analytical and test data underlying the information.

This document may contain or refer to forward looking information, including metallurgical results, mine development plans, and timing of commencement of operations, 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, the metallurgical recovery rates may differ from test results, failure to establish estimated resources and reserves, the grade and recovery of ore which is mined varying from estimates, capital and operating costs varying significantly from estimates, delays in obtaining or failures to obtain required governmental, environmental or other project approvals, inflation, changes in exchange rates, fluctuations in commodity prices, delays in the development of projects and other factors. 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, except as may be required by applicable securities laws, we assume no responsibility to update them or revise them to reflect new events or circumstances.

Further information about our properties, to download a copy of our Annual Report, any technical report, or to access our Press Release Archive please visit www.sedar.com or our website at www.africancopper.com


Ed

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