Northair Reports Maiden Resource Calculation at La Cigarra Silver Project, Mexico
+50 Million Ounces of Silver Resource Grading 76 g/t silver within a Constraining Shell
Conference Call Scheduled for 11:00 am EST, Today
International Northair Mines Ltd. (TSXV: INM) (the "Company" or "Northair") is pleased to announce the results of the maiden NI 43-101 Resource Estimate completed by Arseneau Consulting Services (ACS) in conjunction with JDS Energy and Mining Inc. (JDS) for its La Cigarra silver project located in north central Mexico.
The resource estimate was calculated based on results from 122 of 154 holes totaling 25,576 metres drilled along the open ended La Cigarra mineralized system which has a drilled strike length of at least three (3) kilometres. The 122 holes included in this initial resource estimate were positioned within a potentially surface minable mineralized area comprised of the San Gregorio and Las Carolinas mineralized zones, which combined form a total strike length of 2.1 kilometres within the known three (3) kilometres. The resource estimate was constrained by a WhittleTM pit shell at an economic cutoff grade of 30 g/t of silver. Highlights of the mineral resource estimate are as follows:
- Measured and Indicated mineral resources of 50,494,000 ounces of silver within 20,755,700 tonnes at an average grade of 76 g/t silver;
- Inferred mineral resource of 3,515,900 ounces silver within 1,780,000 tonnes at an average grade of 61 g/t silver;
- Higher than average grade zones outcrop, which could improve the assumed project economics in the early years;
- Significant by-products include 40,100 ounces of gold in the measured and indicated categories as well as appreciable lead and zinc values, as provided in mineral resource estimate tables noted in this press release.
Northair believes that excellent potential to expand the resource exists through exploration and definition drilling along the La Cigarra mineralized system.
"We are very pleased by the results of our initial resource estimate for La Cigarra, particularly the average silver grade," said Fred Hewett, President & CEO of Northair. "Since our first 2010 drill program, the Company has advanced the La Cigarra Project from initial discovery to a +50 million silver resource at an exploration cost of approximately $0.15 per ounce silver. During 2013, Northair plans to continue the aggressive pace of its exploration program to expand the resource and explore other identified exploration targets. Additional studies to establish project economics will continue over the foreseeable future."
Northair will host a conference call and live audio webcast on February 26, 2013 at 8:00 am Pacific Time (11:00 am Eastern Time) to provide a short overview on Northair's La Cigarra silver project and the importance of this maiden resource estimate coupled with the significant exploration potential. Conference call and live audio webcast details are located at the end of this release and on the Northair website below:
Resource Expansion Potential
Considerable resource expansion potential exists within the resource area, which remains open at depth and along strike in both directions. This potential is in part supported by soil sampling over the six (6) kilometre long La Cigarra mineralized system, with La Borracha to the north (where nine (9) drill holes have intercepted significant silver mineralization) and the Las Venadas Zone to the south (which has returned surface silver values of up to 233 g/t silver over 2.5 metres). The defined target zone at Las Venadas covers an area of approximately 230 metres by 90 metres. In addition, numerous other target areas within the remaining 32,000 hectare land package could host significant mineralization as evidenced by a cluster of historic workings and mineralized grab samples obtained from preliminary prospecting.
To view the image of the La Cigarra silver resource, click on the following link:http://www.kootenaysilver.com/i/maps/northair/2013-02-26-La_Cigarra_Conceptual_Pit_PR.jpg
To view the site plan of the San Gregorio Zone, please click on the following link:http://www.kootenaysilver.com/i/maps/northair/2013-02-26_Resource_Drill_Plan_PR.jpg
To view a cross section of San Gregorio section 0+00, please click on the following link:
http://www.kootenaysilver.com/i/maps/northair/2013-02-26_San_Gregorio_CS_PR.jpg
A summary of the mineral resource estimate contained in the resource shell is calculated by ACS at a 30 g/t silver cut-off grade is listed below:
| Category | Tonnes* | Ag (g/t) | Au (g/t) | Pb (%) | Zn (%) | Ag Oz | Au Oz | Pb Lbs | Zn lbs |
|---|---|---|---|---|---|---|---|---|---|
| Measured | 6,235,000 | 65 | 0.06 | 0.10 | 0.16 | 13,090,800 | 12,100 | 13,161,500 | 21,706,600 |
| Indicated | 14,520,700 | 80 | 0.06 | 0.10 | 0.14 | 37,402,800 | 28,100 | 32,924,700 | 45,983,100 |
| M + I | 20,755,700 | 76 | 0.06 | 0.10 | 0.15 | 50,494,000 | 40,100 | 46,086,200 | 67,689,700 |
| Inferred | 1,780,150 | 61 | 0.05 | 0.10 | 0.12 | 3,515,900 | 3,000 | 3,959,300 | 4,865,700 |
The mineral resources of the La Cigarra Project are sensitive to cut-off grade. To illustrate this, the block model quantities and grade estimates within the conceptual pit are presented in the following table at different cut-off grades.
| CLASS | Cut-off | Tonnes (000) | Ag (g/t) | Ag (oz) | Au (g/t) | Pb (%) | Zn (%) |
|---|---|---|---|---|---|---|---|
| Measured | >100 Ag g/t | 803 | 137 | 3,548,500 | 0.08 | 0.14 | 0.17 |
| > 50 Ag g/t | 3,571 | 85 | 9,741,200 | 0.07 | 0.11 | 0.18 | |
| > 40 Ag g/t | 4,753 | 75 | 11,434,300 | 0.06 | 0.11 | 0.17 | |
| >30 Ag g/t | 6,235 | 65 | 13,090,800 | 0.06 | 0.1 | 0.16 | |
| >20 Ag g/t | 8,220 | 56 | 14,676,900 | 0.06 | 0.08 | 0.14 | |
| > 10 Ag g/t | 11,689 | 43 | 16,301,200 | 0.05 | 0.07 | 0.12 | |
| Indicated | >100 Ag g/t | 3,578 | 156 | 17,968,000 | 0.08 | 0.15 | 0.19 |
| > 50 Ag g/t | 9,235 | 104 | 30,834,800 | 0.07 | 0.12 | 0.17 | |
| > 40 Ag g/t | 11,273 | 93 | 33,763,100 | 0.06 | 0.11 | 0.16 | |
| >30 Ag g/t | 14,521 | 80 | 37,402,800 | 0.06 | 0.1 | 0.14 | |
| >20 Ag g/t | 19,539 | 66 | 41,381,600 | 0.06 | 0.09 | 0.13 | |
| > 10 Ag g/t | 27,714 | 51 | 41,381,600 | 0.05 | 0.07 | 0.11 | |
| Inferred | >100 Ag g/t | 160 | 139 | 717,400 | 0.06 | 0.15 | 0.18 |
| > 50 Ag g/t | 936 | 82 | 2,467,000 | 0.06 | 0.12 | 0.15 | |
| > 40 Ag g/t | 1,252 | 73 | 2,920,200 | 0.06 | 0.11 | 0.14 | |
| >30 Ag g/t | 1,780 | 61 | 3,515,900 | 0.05 | 0.1 | 0.12 | |
| >20 Ag g/t | 2,497 | 51 | 4,091,200 | 0.05 | 0.09 | 0.11 | |
| > 10 Ag g/t | 3,386 | 41 | 4,689,300 | 0.05 | 0.08 | 0.09 |
The development of the comparative tables has relied on the work of experts as described in this release. The following factors should also be noted:
- Mineral resources were estimated in conformance with the CIM Mineral Resources definitions referred to in National Instrument 43-101, Standard of Disclosure for Mineral Properties;
- The resource estimate considered the results of 154 drill holes totaling (25,576 metres) and was calculated by using 122 of these holes;
- Mineral resources were estimated by ordinary kriging in 10x10x10 metre blocks. Grades were capped to 500 g/t silver in the high grade portion of the mineralization:
- Mineral resources were classified as Measured if at least three (3) drill holes were found within a 75 x 50 x 25 metre search radius. Blocks were classified as Indicated if two (2) drill holes were found within a 75x50x25 metre radius and block were classified as Inferred if at least three (3) drill holes were found within a 100x75x30 metre search radius;
- The "reasonable prospects for economic extraction" requirement generally implies that the quantity and grade estimates meet certain economic thresholds and that the mineral resources are reported at an appropriate cut-off grade taking into account extraction scenarios and processing recoveries. In order to meet this requirement, ACS considers that major portions of La Cigarra mineralization are amenable for open pit extraction;
- In order to determine the quantities of material offering "reasonable prospects for economic extraction" by an open pit, ACS, with the assistance of JDS, used Whittle(tm) pit optimization software and reasonable mining assumptions to evaluate the proportions of the block model (Measured, Indicated and Inferred blocks) that could be "reasonably expected" to be mined from an open pit;
- The optimization parameters, found in the table below, were selected based on experience and benchmarking against similar projects. The reader is cautioned that the results from the pit optimization are used solely for the purpose of testing the "reasonable prospects for economic extraction" by an open pit and do not represent an attempt to estimate mineral reserves. There are no mineral reserves on the La Cigarra Project. The results are used as a guide to assist in the preparation of a mineral resource statement and to select an appropriate resource reporting cut-off grade.
| Parameter | Value | Unit |
|---|---|---|
| Silver Price | $ 29.20 | US$ per ounce |
| Lead Price | $ 1.00 | US$ per pound |
| Zinc Price | $ 0.95 | US$ per pound |
| Mining Cost | $ 2.00 | US$ per tonne mined |
| Processing (Sulphide material) | $ 15.00 | US$ per tonne of sulphide feed |
| Processing (Oxide Material) | $ 12.00 | US$ per tonne of oxide feed |
| General and Administrative | $ 1.00 | US$ per tonne of feed |
| Overall Pit Slope | 45 | degrees |
| Silver Flotation Recovery | 84 | Percent |
| Lead Flotation Recovery | 75 | Percent |
| Zinc Flotation Recovery | 60 | Percent |
| Silver Leach Recovery | 90 | Percent |
| Lead Payable | 95 | Percent |
| Silver Payable in Lead Conc. | 95 | Percent |
| Zinc Payable | 85 | Percent |
| Silver Payable in Zinc Conc. | 70 | Percent |
| Silver Dore Payable | 100 | Percent |
Conference Call and Webcast Information
Northair will host a conference call and live audio webcast to explain the significance of the maiden resource estimate for the La Cigarra silver project announced today. Conference call and live audio webcast details are below and on the Northair website: www.internationalnorthair.com.
Date: Tuesday, February 26, 2013
Time: 8.00 am Pacific Time (11.00 am Eastern Time)
Dial-In Numbers:
- North American toll-free number: 416-340-2217 or 866-696-5910
- International toll number: 800-8989-6336
- Passcode 4989072
Audio Webcast:
A live audio webcast can be accessed at http://www.gowebcasting.com/4198
Playback Available for Two Weeks Following the Call:
- North American toll-free number: 905-694-9451 or 800-408-3053
- International toll number: 800-3366-3052
- Pass code: 5042006
QA/QC
This news release has been prepared in accordance with Canadian regulatory requirements set out in National Instrument 43-101 and approved by Fred Hewett, the Company's President and CEO, and a Qualified Person under NI 43-101.
The resource estimation work was completed by Dr. Gilles Arseneau, P.Geo. of Arseneau Consulting Services and an independent Qualified Person as defined under NI 43-101.
About International Northair Mines Ltd.
Northair is a mineral exploration company engaged in the acquisition and development of gold and silver properties in Mexico. The Company is currently focused on advancing its La Cigarra silver project located in the state of Chihuahua, Mexico, which currently has a NI 43-101 resource of 50.4 million ounces of silver in the measured & indicated categories grading 76 g/t silver and 3.5 million ounces of silver in the inferred category grading 61 g/t silver. The La Cigarra silver deposit also contains appreciable gold, lead and zinc values.
ON BEHALF OF THE BOARD,
INTERNATIONAL NORTHAIR MINES LTD.
"Fred G. Hewett"
____________________________________
Fred G. Hewett, P.Eng.
President & CEO
For further information please contact Fred Hewett, President & CEO,
Chris Curran, Manager, Corporate Communications or Brent Levenstadt, Investor Relations Associate
at 604-687-7545 or 1-888-338-2200
Website: www.northair.com/international/ Email: info@northair.com
Neither 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 news release.
This news release may contain forward looking statements which are not historical facts, such as ore reserve estimates, anticipated production or results, sales, revenues, costs, or discussions of goals and exploration results, and involves a number of risks and uncertainties that could cause actual results to differ materially from those projected. These risks and uncertainties include, but are not limited to, metal price volatility, volatility of metals production, project development, ore reserve estimates, future anticipated reserves and cost engineering estimate risks, geological factors and exploration results. See Northair's filings for a more detailed discussion of factors that may impact expected results.
This news release does not constitute an offer to sell or solicitation of an offer to sell any securities in the United States. The securities have not been and will not be registered under the United States Securities Act of 1933, as amended (the "U.S. Securities Act") or any state securities laws and may not be offered or sold within the United States or to U.S. Persons unless registered under the U.S. Securities Act and applicable state securities laws or an exemption from such registration is available.