Yale completes metallurgyMarch 13, 2008
YALE COMPLETES PRELIMINARY METALLURGICAL STUDIES AT LA VERDE GRANDE
Yale Resources Ltd. (TSX-V - YLL and Frankfurt - YAB) is pleased to announce that preliminary metallurgical studies on mineralization from within the La Verde Grande Mine has shown that excellent recoveries can be obtained for copper and zinc. Bottle roll tests indicate that recoveries of 84.3 % for copper and 76.5 % for zinc are obtainable. Gold and silver recoveries were not part of this first test.
The study was completed in Hermosillo by Consulores Entalpia who have acted as metallurgical consultants to many of the copper mines in Sonora, including Piedras Verdes (Frontera Copper), Cananea (Peñoles), and La Caridad (Grupo Mexico). The study was performed on approximately 150 kg of material from the lower level of the La Verde Grande Mine, which had an average grade of 2.21 % copper and 0.68 % zinc. Historic metallurgical studies and production data have resulted in a wide variety of results with emphasis on either copper or silver depending on their relative value at the time and always involved the flotation of the oxide mineralization. The most recent, performed in 1981, studied the recovery of silver and gold by floatation with the recovery of copper from the tails. This resulted in total metal recoveries estimated at 81 % for copper, 80 % for silver and 60 % gold - with no consideration for zinc.
In bringing the metallurgical studies to current standards, a key component is to test the viability of a heap leach scenario for the La Verde Grande mineralization. A preliminary column test performed by Yale showed recoveries of 66.61 % copper after 30 days on 30 kg of ‘run of mine’ (no crushing) mineralization. The results of this initial test indicate that better recoveries could be obtained with a longer leach time and that recoveries may also be improved with crushing.
Yale is awaiting recommendations for further studies to determine optimal parameters for heap leaching while also examining the economic viability of conventional milling and processing as an alternate processing route.
“This is a critical step in advancing the La Verde Grande deposit towards feasibility as the combination of favourable preliminary metallurgy and high grades encountered to date together with record metal prices suggests that there is the real potential to define an ore body within the La Verde Project”, stated Ian Foreman, P.Geo., President of Yale Resources.
Ian Foreman, P.Geo, is the Qualified Person, according to National Instrument 43-101, for the La Verde Project and is responsible for the technical data mentioned in this news release. ‘Historic’ data is supplied for reference only and should not be relied upon as it pre-dates NI 43-101.
On behalf of the Board,
“Ian Foreman”
Ian Foreman, P.Geo.
President
For additional information on Yale Resources please call Dave Riccio at 604-678-2531.
The TSX Venture Exchange has not reviewed and does not accept responsibility for the adequacy or accuracy of this release. Statements in this press release, other than purely historical information, including statements relating to the Company’s future plans and objectives or expected results, may include forward-looking statements. Forward-looking statements are based on numerous assumptions and are subject to all of the risks and uncertainties inherent in resource exploration and development. As a result, actual results may vary materially from those described in the forward-looking statements.