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Minefinders Announces Metallurgical Test Results Confirm Excellent Recoveries Of Gold And Silver.

Business Editors

VANCOUVER, B.C.--(BUSINESS WIRE)--Oct. 25, 2000

Minefinders (OTCBB:MNEFF)(TSE:MFL.)

Minefinders Corporation Ltd. (OTCBB:MNEFF)(TSE:MFL.) - Mark H. Bailey, President and CEO, is pleased to report final results from pulp agglomeration column leach testing completed by McClelland Laboratories of Sparks, Nevada.

These results combined with the updated resource calculation (reported in News Release dated September 18, 2000) will be used to provide the basis for additional economic analysis of the Dolores main zone deposit.

The final metallurgical report prepared by McClelland Laboratories emphasizes that "Dolores ores are amenable to pulp agglomeration heap leach treatment." Overall projected recoveries will average 86% - 89% for gold and 57% - 65% for silver. Of particular importance is that "gold recoveries of over 95 percent and silver recoveries of over 80 percent can be achieved from the high-grade pulps in a commercial pulp agglomeration heap leach processing cycle."

The proposed pulp-agglomeration heap leach processing methodology will process the higher grade ore through a mill grinding circuit (approximately 35% of the open pit minable tonnes) then agglomerate the residual pulp with lower grade ore (approximately 65% of open pit minable tonnes) and process by standard heap leach technology. The resource estimation block model shows that between 65% and 70% of the total contained gold and silver metal within the Dolores deposit will be recovered from the high-grade ore at the greater than 95% for gold and greater than 80% for silver recovery rates. This number substantially exceeds recovery rates previously predicted for the high-grade pulped material and in turn should reflect positively in the overall economics of the operation.

Open pit mine modeling will use the 0.5 and 0.6 g/t Aueq cutoff grades with an anticipated mill cutoff grade of between 1.5 g/t and 2.0 g/t Aueq, depending on modeling parameters. At either of these mine cutoff grades the Dolores deposit contains more than 2 million ounces of gold and 110 million ounces of silver and the potential to more than double in size with additional exploration drilling.

McClelland reports that "recovery from high grade pulp is relatively independent of grind size." The grind sizes used in the column leach tests were a relatively coarse P80-212 micrometers (80% passing -65 mesh), and a finer P80-106 micrometers (80% passing -150 mesh) grind size that effectively leached at the same rate for two out of three of the tested zones. Only material sampled from the North Zone showed significantly enhanced recovery from the finer grind size. In the test columns, low-grade ores crushed at 3/8 inch (80% passing -9.5 mm) were combined with the residual high-grade pulp at a relatively high 75:25 low-grade to high-grade ore ratio. Because "there were no percolation, fines migration, or solution channeling problems encountered during percolation leaching of the 75% L.G.: 25% H.G. pulp ore mixtures," the projected commercial heap-leach low-grade to high-grade ratio can be increased resulting in additional recovery efficiency.

Actual projected recoveries assuming a 65:35 low-grade to high-grade ratio and leach times typical of commercial pulp agglomeration heap leach processing were calculated by McClelland Labs from the data obtained from the six completed pulp agglomeration column leach tests. Using the coarser grind size (P80-212 micrometers), overall projected gold recoveries are 91%, 91%, and 75% gold for the South, Central, and North zones respectively. At the finer grind size of (P80 -106 micrometers) projected gold recovery increased to 86% for the North zone. Overall projected silver recoveries at the coarser grind size were 58%, 61%, and 76% for the South, Central, and North zones respectively. Additional testing to optimize recoveries of the high-grade pulped material, and to confirm the efficacy of leaching at the 65:35 low-grade to high-grade ratio are recommended.

The company is proceeding with computer design of a new open-pit mine plan incorporating results of the updated resource model, which includes data from the 5,800 meters of drilling completed this year and the revised metallurgical recoveries. Overall project economics should reflect the impact of the higher grades in the updated resource model as well as the improved metallurgical recoveries.

The Dolores deposit remains open in all directions with excellent potential to more than double the current gold and silver resource. The deposit has continued to increase in size and grade with the completion of each drilling program, now totaling more than 61,000 meters in 230 drill holes, and it is expected to continue to increase in size and grade as the deposit is brought to final feasibility.

On Behalf of the Board of Directors MINEFINDERS CORPORATION LTD.

Mark H. Bailey, President and Chief Executive Officer

Safe Harbor Statement under the United States Private Securities Litigation Act of 1995: Statements in this release that are forward-looking are subject to various risks and uncertainties concerning the specific factors identified above and in the corporation's periodic filings with the Ontario Securities Commission and the U. S. Securities Exchange Commission. Such information contained herein represents management's best judgment as of the date hereof based on information currently available. The corporation does not intend to update this information and disclaims any legal liability to the contrary.
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