Corvus Gold final leach gold recovery results average 88% for Mayflower deposit, North Bullfrog Project, Nevada
Friday, Jan 18, 2013
VANCOUVER, Jan. 17, 2013 /PRNewswire/ - Corvus Gold Inc. ("Corvus" or the "Company") - (TSX: KOR), (OTCQX: CORVF) announces the final results of a series of column leach tests on large diameter core sample composites from the Mayflower deposit at the North Bullfrog Project, Nevada. The final results averaged 88% gold recovery at a crush size of nominally 80% passing 19mm (-3/4 inch), which represents a 10% greater gold recovery than the 78% gold recovery assumed in the December 6, 2012 Preliminary Economic Assessment (PEA). These encouraging results suggest that the potential exists to operate the Mayflower project on a Run Of Mine (ROM) basis, although at lower recoveries than would be achieved by crushing.
The impact of ROM processing could significantly reduce both capital and operating costs per tonne for the Mayflower deposit where gold production is anticipated for late 2014. The Company is currently conducting large ROM testing on large diameter material and working with mining consultants on optimizing blasting configurations to maximize fragmentation to assess this option.
The final recovery data (Table 1) support the high gold leachability of the Mayflower oxide material even at grades as low as 0.16 g/t. The impact of this increased recovery data will be integrated into the Company's upcoming Mayflower Feasibility Study scheduled for the first quarter of 2013.
Carl Brechtel, COO of Corvus, stated: "The current gold recovery results continue to be very encouraging and fully support the Mayflower deposit as an attractive mining project with potential to continue to improve. These results, linked with the discovery of the Yellow Jacket high-grade zone in the North Area which has yet to be incorporated into the resource base, provide high potential for continued enhancement of the overall North Bullfrog project in 2013."
In addition, a series of ROM vat leach tests are ongoing on particles at 75 mm, 150 mm and 200 mm to provide data to evaluate gold recovery at larger particle size. These results will be integrated with further column tests at larger crush size and blasting studies to fully assess operating the Mayflower project as a ROM operation which could provide a major cost and operational benefit.
About the North Bullfrog Project, Nevada
Corvus controls 100% of its North Bullfrog Project, which covers approximately 68 square kilometres in southern Nevada just north of the historic Bullfrog gold mine formerly operated by Barrick Gold Corp. The property package is made up of a number of private mineral leases of patented federal mining claims and 758 federal unpatented mining claims. The project has excellent infrastructure, being adjacent to a major highway and power corridor.
The project currently includes numerous prospective gold targets with four (Mayflower, Sierra Blanca, Jolly Jane and Connection) containing an estimated Oxidized Indicated Resource of 27 Mt at an average grade of 0.28 g/t gold for 246,810 ounces of gold and an Oxidized Inferred Resource of 234.5 Mt at 0.18 g/t gold for 1,387,870 ounces of gold (both at a 0.1 g/t gold cutoff), with appreciable silver credits. Unoxidized Inferred mineral resources are 221.6 Mt at 0.19 g/t for 1,361,000 ounces of gold (at a 0.1 g/t gold cutoff).
Mineralization occurs in two primary forms: (1) broad stratabound bulk-tonnage gold zones such as the Sierra Blanca and Jolly Jane systems; and (2) moderately thick zones of high-grade gold and silver mineralization hosted by structural zones with breccias and quartz-sulphide vein stockworks such as the Mayflower and Yellowjacket targets. The Company is actively pursuing both types of mineralization.
A video of the North Bullfrog project showing location, infrastructure access, and 2010 winter drilling is available on the Company's website at http://www.corvusgold.com/investors/video/.
Qualified Person and Quality Control/Quality Assurance
Jeffrey A. Pontius (CPG 11044), a qualified person as defined by National Instrument 43-101, has supervised the preparation of the scientific and technical information (other than the resource estimate) that form the basis for this news release and has approved the disclosure herein. Mr. Pontius is not independent of Corvus, as he is the CEO and holds common shares and incentive stock options.
Carl E. Brechtel, PE, a qualified person as defined by National Instrument 43-101, is responsible for planning and execution of the technical and engineering studies at North Bullfrog. He is responsible for the preparation of this news release and has approved the disclosure herein. He has over 30 years of experience in the mining industry, is a registered professional engineer in the States of Colorado and Nevada, and is a Registered Member of SME. Mr. Brechtel is not independent of Corvus, as he is the COO and holds common shares and incentive stock options.
Mr. William J. Penstrom, Jr., a consulting process engineer and President of Pennstrom Consulting, Inc., has acted at the Qualified Person, as defined by NI 43-101, for evaluation of the metallurgical testing data presented herein. He has over 30 years of experience in mineral process design and operation, and has been an independent process and metallurgical consultant for the mining industry for the last 10 years. He is a Registered Member of the Society of Mining, Metallurgy and Exploration (SME Member # 2503900). Mr. Pennstrom and Pennstrom Consulting Inc. are both independent of the Company under NI 43-101.
Mr. Gary Giroux, M.Sc., P. Eng (B.C.), a consulting geological engineer employed by Giroux Consultants Ltd., has acted as the Qualified Person, as defined in NI 43-101, for the Giroux Consultants Ltd. mineral resource estimate. He has over 30 years of experience in all stages of mineral exploration, development and production. Mr. Giroux specializes in computer applications in ore reserve estimation, and has consulted both nationally and internationally in this field. He has authored many papers on geostatistics and ore reserve estimation and has practiced as a Geological Engineer since 1970 and provided geostatistical services to the industry since 1976. Both Mr. Giroux and Giroux Consultants Ltd. are independent of the Company under NI 43-101.
The work program at North Bullfrog was designed and is supervised by Russell Myers (CPG 11433), President of Corvus, a Qualified Person defined by NI 43-101, and by Mark Reischman, Corvus Nevada Exploration Manager, who are responsible for all aspects of the work, including the quality control/quality assurance program. On-site personnel at the project log and track all samples prior to sealing and shipping. Quality control is monitored by the insertion of blind certified standard reference materials and blanks into each sample shipment. All resource sample shipments are sealed and shipped to ALS Chemex in Reno, Nevada, for preparation and then on to ALS Chemex in Reno, Nevada, or Vancouver, B.C., for assaying. ALS Chemex's quality system complies with the requirements for the International Standards ISO 9001:2000 and ISO 17025:1999. Analytical accuracy and precision are monitored by the analysis of reagent blanks, reference material and replicate samples. Finally, representative blind duplicate samples are forwarded to ALS Chemex and an ISO compliant third party laboratory for additional quality control. McClelland Laboratories Inc. prepared composites from duplicated RC sample splits collected during drilling. Bulk samples were sealed on site and delivered to McClelland Laboratories Inc. by ALS Chemex or Corvus personnel. All metallurgical testing reported here was conducted or managed by McClelland Laboratories Inc.
About Corvus Gold Inc.
Corvus Gold Inc. is a resource exploration company, focused in Nevada, Alaska and Quebec, which controls a number of exploration projects representing a spectrum of early-stage to advanced gold projects. Corvus is focused on advancing its 100% owned Nevada, North Bullfrog project towards a potential development decision and continuing to explore for new major gold discoveries. Corvus is committed to building shareholder value through new discoveries and leveraging noncore assets via partner funded exploration work into carried and or royalty interests that provide shareholders with exposure to gold production.
On behalf of
Corvus Gold Inc.
(signed) Jeffrey A. Pontius
Jeffrey A. Pontius,
Chief Executive Officer
SOURCE Corvus Gold Inc.