VANCOUVER, Nov. 30 /PRNewswire/ -- Northgate Minerals Corporation (TSX: NGX, NYSE Amex: NXG) is pleased to report assay results for the final 16 drill holes from its infill diamond drilling program at the Kemess Underground Project located five kilometres ("km") north of its Kemess South mine in north-central British Columbia.
Drilling Highlights - Hole KN-10-13 intersected 80.0 metres ("m") of 2.4 grams per tonne ("g/t") gold and 0.78% copper within a broader interval of 185.6 m, which returned 1.556 g/t gold and 0.571% copper. - Hole KN-10-17 intersected 59.5 m of 1.15 g/t gold and 0.516% copper within a broader interval of 328.5 m, which returned 0.609 g/t gold and 0.268% copper. - Hole KN-10-25A intersected 46.0 m of 1.43 g/t gold and 0.489% copper within a broader interval of 266 m, which returned 0.559 g/t gold and 0.261% copper. - A higher grade zone in the northeast quadrant has been identified and is continuous and supported by several holes, including a previously- released hole KN-10-03, which returned one of the best intercepts in the Kemess resource database. - The weighted average grade of all holes drilled in the 2010 program were higher than previous resource block estimates in the block cave zone by 12% for gold and 3.5% for copper.
"We are excited to have completed the 2010 drill program at Kemess Underground, which has exceeded our expectations" commented Ken Stowe, President and Chief Executive Officer. "Now that all assay results are in hand, we see further confirmation with hole KN-10-13 that a compact, continuous higher grade zone exists beneath the eastern third of the resource area currently being considered for a bulk underground mining operation. The 2010 results from the higher grade sector consistently exceed grades for both copper and gold when compared to the 2005 resource model. We now look forward to completing a new underground resource estimate, which is expected early in the first quarter of 2011 and will support studies to determine the economics of the potential underground mine at Kemess."
Overview of the Kemess Underground Project and 2010 Exploration Program
The Kemess Underground diamond drill program, the final results of which are reported herein, was conducted in order to better define the 70+ million tonne proposed block cave portion of the Kemess North deposit estimated from previous drilling to contain in excess of 1.4 million ounces of gold and 500 million pounds of copper.
The Kemess Underground drill program was also designed to document the geotechnical characteristics of the higher grade core to determine the potential for large scale, underground, bulk mine production that could be milled at the existing Kemess infrastructure and utilize the existing permitted tailings capacity in the Kemess South pit.
The 2010 program in its entirety consisted of 30 drill holes totalling 16,439 m. Drilling contractors were successful in completing 26 holes to targeted depths. Only one drill hole from the program failed to intersect mineralization (hole 22), confirming the eastern fault-bound margin of the deposit. Geotechnical analysis is underway and the assay and geologic results from the 2010 program are being combined with previous drilling results in order to update the resource estimate for the 70+ million tonne, proposed block cave portion of the deposit. This updated resource estimate is expected to be released with Northgate's annual resource and reserve statement in the first quarter of 2011.
Figure 1: Plan showing collar locations of the final 16 holes drilled in 2010 relative to previous collars relative to block cave area outline.
http://www.northgateminerals.com/Theme/Northgate/files/Releases/11-30F1.gif
Figure 2: Plan showing area of resource within an interpreted 1.0 g/t gold grade shell relative to block cave area outline.
http://www.northgateminerals.com/Theme/Northgate/files/Releases/11-30F2.gif 2010 Drilling Results
Table 1 below summarizes intersections for the final 16 holes of the 2010 drilling campaign. Intervals have been selected based on their position relative to a block cave mining outline designed from scoping study work completed earlier in 2010.
Table 1: Assay Results from 2010 Diamond Drill Holes - Final 16 ------------------------------------------------------------------------- Hole From (m) To (m) Interval (m) Cu % Au (g/t) ------------------------------------------------------------------------- KN-10-06 236.0 602.0 366.0 0.249 0.481 including 384.0 454.9 70.9 0.362 0.847 ------------------------------------------------------------------------- ------------------------------------------------------------------------- KN-10-11 365.0 536.0 171.0 0.242 0.398 including 409.0 460.0 51.0 0.275 0.528 ------------------------------------------------------------------------- ------------------------------------------------------------------------- KN-10-13 211.0 504.0 293.0 0.403 1.051 including 279.0 464.6 185.6 0.571 1.556 Including 369.0 449.0 80.0 0.783 2.397 ------------------------------------------------------------------------- ------------------------------------------------------------------------- KN-10-15 275.8 534.0 258.2 0.325 0.524 including 400.0 430.0 30.0 0.577 1.258 Including 458.0 482.0 24.0 0.625 0.897 ------------------------------------------------------------------------- ------------------------------------------------------------------------- KN-10-16 321.9 675.0 353.1 0.196 0.443 including 492.5 580.5 88.0 0.372 0.895 including 522.5 544.5 22.0 0.479 1.164 ------------------------------------------------------------------------- ------------------------------------------------------------------------- KN-10-17 214.5 543.0 328.5 0.268 0.609 including 312.0 471.0 159.0 0.402 0.931 including 350.5 410.0 59.5 0.516 1.149 ------------------------------------------------------------------------- ------------------------------------------------------------------------- KN-10-18 261.0 617.0 356.0 0.187 0.331 including 407.0 429.0 22.0 0.302 0.712 ------------------------------------------------------------------------- ------------------------------------------------------------------------- KN-10-19 190.0 343.8 153.8 0.268 0.772 including 240.0 343.8 103.8 0.275 0.930 ------------------------------------------------------------------------- ------------------------------------------------------------------------- KN-10-20 276.0 620.0 344.0 0.204 0.351 including 286.0 361.6 75.6 0.310 0.494 ------------------------------------------------------------------------- ------------------------------------------------------------------------- KN-10-21 196.9 356.3 159.44 0.121 0.337 including 196.9 228.0 31.1 0.098 0.352 and 324.2 356.3 32.1 0.471 0.968 ------------------------------------------------------------------------- ------------------------------------------------------------------------- KN-10-23 231.0 525.0 294.0 0.233 0.442 including 261.0 285.0 24.0 0.318 0.641 Including 397.0 423.0 26.0 0.281 0.473 ------------------------------------------------------------------------- ------------------------------------------------------------------------- KN-10-24 235.6 606.6 371.0 0.19 0.417 Including 487.9 527.0 39.1 0.307 0.729 ------------------------------------------------------------------------- ------------------------------------------------------------------------- KN-10-25A 308.0 574.0 266.0 0.261 0.559 Including 447.0 491.0 46.0 0.489 1.428 ------------------------------------------------------------------------- ------------------------------------------------------------------------- KN-10-26 267.0 564.0 297.0 0.265 0.616 including 426.0 468.0 42.0 0.338 0.839 ------------------------------------------------------------------------- 2010 Results Compared to 2005 Open Pit Resource
Comparison of all 2010 drill hole results against the previous 2005 Kemess North resource model shows that the current program's results are, on average, 12% higher for gold and 3.5% higher for copper, using a weighted average of resource blocks captured by a 20 x 20 m prism centered on each drill hole trace.
While the 2010 results show both positive and negative variance from the 2005 resource model, the comparison demonstrates that existing 2005 estimates are conservative globally and that a higher grade zone in the northeast quadrant, defined by holes KN-10-03, 05, 07A, 09A, 10, and 13, was significantly underestimated. These variations are believed to be attributable to the 2005 resource model being based on interpolation from wider-spaced drilling that was unconstrained with respect to important grade domains, such as different alteration and or geological controls, whereas the 2010 results now recognize these factors within the resource. With the benefit of the information provided by the 2010 results, it appears that the 2005 resource model tended to overestimate low grade regions and underestimate high grade regions. Work is now underway to update the resource for an underground mining scenario and to account for the distinct grade domains that exist in this subsection of the Kemess North deposit.
Appendix 1: All 2010 Diamond Drill Hole Collar Locations ------------------------------------------------------------------------- East- North- Eleva- Azi- Total Hole # ing ing Nad83E Nad83N tion muth Dip Depth Comment ------------------------------------------------------------------------- KN-10-01 10560 16182 636503 6326501 1681 255 -70 45.0 Abandoned ------------------------------------------------------------------------- KN-10-01A 10560 16182 636504 6326502 1681 262 -75 602.0 ------------------------------------------------------------------------- KN-10-02 10513 16005 636462 6326323 1705 257 -72 642.0 ------------------------------------------------------------------------- KN-10-03 10706 16394 636642 6326718 1578 252 -71 504.0 ------------------------------------------------------------------------- KN-10-04 10402 16298 636341 6326612 1712 253 -69 633.0 ------------------------------------------------------------------------- KN-10-05 10713 16343 636651 6326668 1587 253 -71 561.0 ------------------------------------------------------------------------- KN-10-06 10434 16221 636376 6326537 1703 246 -71 663.0 ------------------------------------------------------------------------- KN-10-07 10599 16370 636536 6326691 1606 248 -70 339.0 Abandoned ------------------------------------------------------------------------- KN-10-07A 10599 16370 636536 6326691 1606 248 -70 532.0 ------------------------------------------------------------------------- KN-10-08 10494 16244 636435 6326562 1685 176 -76 612.0 ------------------------------------------------------------------------- KN-10-09 10493 16246 636434 6326563 1685 0 -75 120.5 Abandoned ------------------------------------------------------------------------- KN-10-09A 10494 16246 636435 6326563 1685 3 -74 620.0 ------------------------------------------------------------------------- KN-10-10 10735 16256 636675 6326582 1616 247 -66 575.0 ------------------------------------------------------------------------- KN-10-11 10753 16184 636210 6326494 1647 257 -69 575.0 ------------------------------------------------------------------------- KN-10-12 10604 16140 636549 6326461 1681 358 -58 624.0 ------------------------------------------------------------------------- KN-10-13 10624 16307 636563 6326629 1620 262 -69 549.0 ------------------------------------------------------------------------- KN-10-14 10264 16146 636209 6326456 1786 332 -67 714.0 ------------------------------------------------------------------------- KN-10-15 10647 16226 636588 6326548 1647 257 -69 584.0 ------------------------------------------------------------------------- KN-10-16 10267 16147 636212 6326457 1786 25 -69 708.0 ------------------------------------------------------------------------- KN-10-17 10554 16343 636492 6326662 1636 252 -65 612.0 ------------------------------------------------------------------------- KN-10-18 10267 16141 636211 6326451 1786 192 -68 708.0 ------------------------------------------------------------------------- KN-10-19 10688 16410 636624 6326733 1579 251 -71 527.0 ------------------------------------------------------------------------- KN-10-20 10411 16027 636359 6326342 1722 252 -70 762.0 ------------------------------------------------------------------------- KN-10-21 10783 16319 636721 6326646 1582 252 -77 477.0 ------------------------------------------------------------------------- KN-10-22 10762 16389 636698 6326715 1574 249 -80 485.0 ------------------------------------------------------------------------- KN-10-23 10355 16184 636298 6326497 1738 247 -71 671.0 ------------------------------------------------------------------------- KN-10-24 10372 16109 636318 6326423 1728 255 -75 654.0 ------------------------------------------------------------------------- KN-10-25 10464 16137 636405 6326457 1699 255 -75 100.6 Abandoned ------------------------------------------------------------------------- KN-10-25A 10461 16141 636406 6326457 1699 253 -74 619.0 ------------------------------------------------------------------------- KN-10-26 10520 16255 636461 6326573 1673 239 -72 621.0 ------------------------------------------------------------------------- Quality Control - Analyses and Sample Location
Details of quality assurance/quality control procedures for sample analysis and drill hole survey methodology are reported in detail in the Canadian National Instrument 43-101 Standards of Disclosure for Mineral Projects ("NI 43-101") compliant Technical Report filed on SEDAR (http://www.sedar.com/) on May 6 2005. All 2010 drill holes have had their down hole surveys completed by non-magnetic based instruments such as gyroscope or DeviFlex.
Qualified Persons
The program design, implementation, quality assurance/quality control and interpretation of the results are under the control of Northgate's geological staff, which includes a number of individuals who are qualified persons as defined under NI 43-101. Carl Edmunds, PGeo, Northgate's Exploration Manager, has reviewed the technical contents of this release.
Note to Investors:
The terms "Qualified Person", "Mineral Reserve", "Proven Mineral Reserve", "Probable Mineral Reserve", "Mineral Resource", "Measured Mineral Resource", "Indicated Mineral Resource", and "Inferred Mineral Resource" used in this news release are defined in accordance with NI 43-101.
Northgate Minerals Corporation is a gold and copper producer with mining operations, development projects and exploration properties in Canada and Australia. Our vision is to be the leading intermediate gold producer by identifying, acquiring, developing and operating profitable, long-life mining properties.
Cautionary Note Regarding Forward-Looking Statements and Information:
This Northgate press release contains "forward-looking information", as such term is defined in applicable Canadian securities legislation and "forward-looking statements" within the meaning of the United States Private Securities Litigation Reform Act of 1995, concerning Northgate's future financial or operating performance and other statements that express management's expectations or estimates of future developments, circumstances or results. Generally, forward-looking information can be identified by the use of forward-looking terminology such as "expects", "believes", "anticipates", "budget", "scheduled", "estimates", "forecasts", "intends", "plans" and variations of such words and phrases, or by statements that certain actions, events or results "may", "will", "could", "would" or "might" "be taken", "occur" or "be achieved". Forward-looking information is based on a number of assumptions and estimates that, while considered reasonable by management based on the business and markets in which Northgate operates, are inherently subject to significant operational, economic and competitive uncertainties and contingencies. Northgate cautions that forward-looking information involves known and unknown risks, uncertainties and other factors that may cause Northgate's actual results, performance or achievements to be materially different from those expressed or implied by such information, including, but not limited to gold and copper price volatility; fluctuations in foreign exchange rates and interest rates; the impact of any hedging activities; discrepancies between actual and estimated production, between actual and estimated reserves and resources or between actual and estimated metallurgical recoveries; costs of production; capital expenditure requirements; the costs and timing of construction and development of new deposits; and the success of exploration and permitting activities. In addition, the factors described or referred to in the section entitled "Risk Factors" in Northgate's Annual Information Form for the year ended December 31, 2009 or under the heading "Risks and Uncertainties" in Northgate's 2009 Annual Report, both of which are available on the SEDAR website at http://www.sedar.com/, should be reviewed in conjunction with the information found in this press release. Although Northgate has attempted to identify important factors that could cause actual results, performance or achievements to differ materially from those contained in forward-looking information, there can be other factors that cause results, performance or achievements not to be as anticipated, estimated or intended. There can be no assurance that such information will prove to be accurate or that management's expectations or estimates of future developments, circumstances or results will materialize. Accordingly, readers should not place undue reliance on forward-looking information. The forward-looking information in this press release is made as of the date of this press release, and Northgate disclaims any intention or obligation to update or revise such information, except as required by applicable law.
Cautionary Note to US Investors Regarding Mineral Reporting Standards:
Northgate prepares its disclosure in accordance with the requirements of securities laws in effect in Canada, which differ from the requirements of U.S. securities laws. Terms relating to mineral resources in this press release are defined in accordance with National Instrument 43-101-Standards of Disclosure for Mineral Projects under the guidelines set out in the Canadian Institute of Mining, Metallurgy, and Petroleum Standards on Mineral Resources and Mineral Reserves. The Securities and Exchange Commission (the "SEC") permits mining companies, in their filings with the SEC, to disclose only those mineral deposits that a company can economically and legally extract or produce. The Company uses certain terms, such as, "measured mineral resources" "indicated mineral resources", "inferred mineral resources" and "probable mineral reserves", that the SEC does not recognize (these terms may be used in this press release and are included in the Company's public filings which have been filed with securities commissions or similar authorities in Canada).
Northgate Minerals Corporation
CONTACT: Ms. Keren R. Yun, Director, Investor Relations, Tel:
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