DUMONT NICKEL INC. (DNI : TSX-Ven, DG7 : Frankfurt)
TORONTO, April 28 /CNW/ - Dumont Nickel Inc. (DNI:TSX-Ven, DG7:FSE) is pleased to announce that its first set of bioleaching tests have been completed and that the testwork reported good metal extraction recoveries from representative samples of black shale from its polymetallic black shale projects in the Athabasca region, Alberta. Recoveries reported are initial results to be optimized during future additional testwork.
Bioleaching, conducted at the Bureau de Recherches Géologiques et Minières (BRGM), France, reported recoveries as follows: Mo-15.6%; Ni-88.4%; U-88%; V-5.8%; Zn-82.8%; Co-88.1% (Cu, Cd and Li were not measured).
The recoveries reported are significant as they demonstrate that metals can be readily extracted from the black shales via bioleaching; and that recoveries are high enough to compel expansion of the testwork to advance toward scaled up benchtests and column leaching. Dumont considers the current bioleaching results to be a milestone step forward toward development of its polymetallic black shale projects.
BRGM also completed a duplicate parallel test without the addition of bio-organisms, to evaluate effects of biotic intermediation on metals recoveries. Metal recoveries measured from the abiotic leaching testwork are as follows: Mo-2.5%; Ni-86.6%; U-81.9%; V-8.3%; Zn-83.7%; Co-83.2%; Cu-49.4%.
The test results are consistent with results from Dumont's sulphuric acid leaching testwork (announced in press Mar4/10) and serve to reiterate that most of the metals quickly solubilize under acid conditions. The bioleaching testwork concluded that while biological activity may not be as instrumental as anticipated for metals solubilization, it is most likely responsible for improvement in metal yields during leaching.
Dumont engaged BRGM to conduct the bioleaching testwork as a first step toward determining amenability of its polymetallic black shales to bioleaching for the collective recovery of metals. BRGM is France's leading Earth Sciences public institution, recognized worldwide for its expertise in biohydrometallurgy and the development of innovative processes applied to industrial scale bioleaching of metals from sulphides. The Alberta black shales' amenability to bioleaching has never previously been tested, and the current study is intended as an initial step toward broader testwork to follow.
Three samples of a polymetallic black shale, collected by Dumont during its 2009 field program from its Property, were submitted to BRGM in October 2009. Only one of the samples (09ASH004, 1330g) was tested, duplicate subsamples from which were also tested by Dumont during its sulphuric acid leaching testwork (results reported in press Mar4/2010). Bioleaching was conducted using duplicate 200gm charges during apprx 15 days of leaching at substantially constant pH of 1.8, at 40C and 3% solids. A bacterial culture from BRGM's acidophilic culture bank was used during the tests. Considering that the culture had previously been adapted to grow on a copper concentrate, copper recovery from Dumont's black shale could not be measured during the biotic leaching.
Considerable other work is in progress which are expected to be completed shortly. This work includes (i) bioleaching testwork being conducted by the Alberta Research Council relying on bio-organisms cultured from the Alberta black shales, and (ii) Stage-2 sulphuric acid leaching testwork conducted under Dumont's direction to expand on previous tests results which were announced in its Mar4/2010 press. Results from the foregoing work will be announced once the work is completed and data verification/checking have been concluded.
Encouraged by the leaching results, Dumont has started planning for a 2010-2011 winter drilling program to collect additional material for expanded leaching testwork and to commence upgrading its two Potential Mineral Deposits identified at the Buckton and Asphalt Zones to classified resources (see NI-43-101 Technical Report for the projects available from www.sedar.com and www.dumontnickel.com). A summer 2010 surface sampling program is also planned to collect additional sample material for testwork in progress.
The Qualified Person (QP) in connection with this press release and in respect of the Alberta polymetallic black shale projects is Shahé F.Sabag PGeo, President and CEO of Dumont, who is responsible for verification and quality assurance of the exploration data and analytical results set forth in this release. The leaching and analyses reported herein were performed by BRGM, France. Internal analytical control standards and blanks were relied upon by BRGM during its analytical work. The Alberta Research Council has recently changed its name to Alberta Innovates Technology Futures.
Dumont continues to focus its efforts on its polymetallic black shale Properties in Alberta, and its carried interest in the recent diamond discovery from its Attawapiskat Property, Ontario.
Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.
DNI - TSX Venture
DG7 - Frankfurt
SOURCE DNI Metals Inc.
For further information: For further information: Dumont Nickel Inc. - Shahe Sabag, President & CEO or Denis Clement, Chairman, (416) 595-1195, email firstname.lastname@example.org. Also visit www.dumontnickel.com