Northgate Minerals Successfully Completes 2010 Diamond
Drill Program at Kemess Underground
Northgate Minerals
Corporation () 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.
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.
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 No. 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 (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 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).