🕐27.05.11 - 02:00 Uhr

UNDERGROUND DELINEATION DRILLING AT NORTHGATE MINERALS YOUNG-DAVIDSON MINING PRO
JECT CONFIRMS ZONE GEOMETRY AND GRADE



Northgate Minerals

Dear Northgate Minerals Corporation E-mail Alert Subscribers,

Northgate Minerals Corporation has added a new press release to its web site.

For full details please visit the Northgate web site at:

Underground Delineation Drilling at Northgate Minerals Young-Davidson Mining Project Confirms Zone Geometry and Grade

Results Show Potential for Higher "As Mined" Grade from the Underground

VANCOUVER, May 26, 2011 /CNW/ - Northgate Minerals Corporation (TSX: NGX, NYSE Amex: NXG) is pleased to announce results from a highly successful underground delineation drill program at its 100% owned Young-Davidson Mining Project located in northern Ontario.

Delineation drilling was initiated to define the stope limits for underground mining within the Upper Boundary Zone ("UBZ").

Results from the drill program have confirmed the grade, continuity and width of the UBZ, which contains 3.64�million tonnes of ore and is scheduled for mining in the early years of underground production.

Young-Davidson is currently forecasting an initial 15-year mine-life with production commencing in 2012 from a small open pit before mining moves underground in 2014.

The area of delineation drilling covers approximately half of the ore tonnage in the UBZ.

UBZ Drill Highlights

  • The UBZ delineation drill program consisted of 66 holes with much closer-spaced drilling than what was used to develop the initial reserve.

    When combined with the historic "as mined" ore grade on the property of 3.39 grams per tonne (g/t), results continue to suggest a strong probability that the ore grade will be closer to the historic "as mined" grade when the underground orebody is actually mined.�
  • Of the 66 holes that were drilled in the UBZ, 26 holes returned a significant result of greater than 95 gram-metres and 70% of the holes returned greater than 50 gram-metres.
  • Hole YR-36: returned 11.13 g/t uncut over 44.0 metres ("m") (estimated 37.0 m true thickness).
  • Hole YR-17: returned 6.34 g/t uncut over 44.0�m (estimated 43.6 m true thickness).
  • Hole YR-16: returned 5.32 g/t over 54.8 m (estimated 45.9 m true thickness).
  • Hole YM10-16: returned 4.64 g/t over 58.8 m (estimated 51.3 m true thickness).
  • Drill results reported herein will be used to update reserve and resource estimates at the end of the year.

"The delineation drill program within the Upper Boundary Zone has been extremely successful" commented Ken Stowe, President and CEO.

"Results from this delineation program are essential as we move closer to our first gold pour in 2012, as this information gives us confidence in the orebody, confirming the grade, continuity and width of the zone.

In addition, the comparison between cut and uncut drill results from the recent drilling continues to indicate that there is strong potential for the actual "as mined" grade of the current underground reserve to be up to 10% higher than our current reserve grade, which we will look for when the first underground ore is delivered to the mill in 2014."

UBZ Delineation Drill Program

The UBZ delineation drill program began in 2008.

Results from the 2008 drill program were used in the current reserve and resource estimate, but have not been individually reported before.

The program was put on hold in 2009 and part of 2010 as Northgate had sufficient drill information to form its initial proven and probable reserve estimate of 2.8�million ounces of gold1.

Drilling re-commenced in the fall of 2010 with approximately 6,350 m drilled.

In total, 66�holes have been completed (28 NQ and 38 BQ diameter core holes) in the near-surface portion of the UBZ.� These holes are required to define final stoping boundaries with increased resolution and to plan for an efficient and safe mining sequence over the life of the mine.

The UBZ in relation to the current Young-Davidson reserve is shown on the longitudinal section in Figure 1.� The UBZ is located on the structural footwall of a steeply south-dipping syenite contact with meta-sediments over an area equivalent to three hectares.

The area of infill drilling covers approximately half of the ore tonnage in the UBZ (see Figure 2).

The mineralization style is disseminated with pyrite associated with sheeted quartz-pyrite veinlets in well developed potassic alteration.� Delineation drilling has been conducted on sections spaced 15 m to 30�m apart from ramp access located 50 m - 70 m in the footwall of the mineralization.

Previous drilling completed to develop the current reserve was wider-spaced (30 m to 45 m centres).

Of the 66 holes completed from the UBZ delineation program, 26 holes returned intervals greater than 95 gram-metres and are presented in Table 1 (in bold).

Complete drill results can be found in Appendix 1 at the end of this press release.� Results are presented as interval totals for cut (to 20 g/t gold) and uncut analyses.

Delineation drilling for the near-surface sector of the UBZ has been highly successful confirming the grade, continuity and widths of the original resource model and has added new resource potential in the footwall of the UBZ (see Figures 3 - 7) as shown by the red lines appearing outside of the resource outline (in magenta).

Uncut delineation drill results averaged 3.76 g/t gold or 3.39 g/t gold when cut to 20�g/t.� The 11% difference between cut and uncut assays is consistent with the difference noted in the wider-spaced exploration drilling that was used to generate the 2.8 million ounce reserve at Young-Davidson.

Capping is a technique that is employed in the estimation of resources and reserves to apply a margin of conservation to these estimates in the event that higher grade nuggets are disproportionately represented in the sparse sampling.

The fact that the difference between cut and uncut grades continues to be the same in the closer-spaced delineation drilling that was recently completed combined with the fact that the historic "as mined" grade on the property was 12.7% higher than the current reserve grade, suggests the strong possibility that "as mined" ore grades from the underground orebody will exceed the current reserve grade.

Next Steps

Results from this drill program will be incorporated into the annual reserve and resource update at the end of the year.

Delineation drilling on the property is ongoing and future efforts will focus on the upper part of the Lucky Zone ore lenses.

Figure 1 - Young-Davidson Longitudinal Section (looking north).

UBZ in red with black outline.

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig1.JPG

Figure 2 - Young-Davidson Upper Boundary Zone

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig2.JPG

Figures 3 - 7 illustrate each drilling section through the UBZ confirming the original geometry and widths determined from the initial 2008 resource work.

The red lines are the mineralized portions of the drill holes reported in Table 1 and Appendix 1, while magenta shows the resource outline for the UBZ.

Mineralized portions of the drill holes appearing outside of the resource outline demonstrate new resource potential in the footwall of the UBZ.

At the west end of the resource, there is a post-mineral diabase dyke, which is actually located in a slightly lower position than originally modeled.

Table 1: Selected Assay Results from UBZ Delineation Drill Program (>95 gram-metres in bold)

Hole ID From
(m)
To
(m)
Interval
(m)
True
Thickness
(m)
Gold Uncut
(g/t)
Gold Cut
20 g/t
Comment
YM10-13 35.7 78.1 42.4 38.9 3.41 2.85 Upper UBZ
incl 35.7 51.5 15.8 14.5 5.84 4.34
incl 65.5 78.1 12.6 11.6 3.75 3.75
YM10-15 38.0 52.5 14.5 14.1 1.26 1.26 Upper UBZ
incl 38.0 46.5 8.5 8.2 8.50 8.50 Upper UBZ
65.0 81.8 16.8 16.5 1.46 1.46 Upper UBZ

97.5 123.5 26.0 25.5 3.86 3.86 Upper UBZ
YM10-16 10.3 12.4 2.1 1.8 3.65 3.65 UBZ Footwall

28.3 30.2 1.9 1.6 5.58 5.58 UBZ Footwall

57.8 116.6 58.8 51.3 4.64 4.64
incl 59.9 109.0 49.1 42.7 5.27 5.27
incl 82.3 104.5 22.2 19.3 6.43 6.43
YM10-20 59.5 113.6 54.1 52.0 4.32 2.48
incl 59.5 77.5 18.0 17.3 9.78 4.24
incl 82.9 98.3 15.4 14.8 2.51 2.51
incl 102.6 108.8 6.2 6.0 2.45 2.45
YM10-21 47.5 52.0 4.5 4.3 5.22 5.22

58.0 61.0 3.0 2.9 4.34 4.34

80.5 113.3 32.8 31.4 4.27 3.53
YM10-23 64.0 68.5 4.5 4.0 3.02 3.02
78.3 104.0 25.7 22.9 6.26 6.26
YM10-24 51.7 104.1 52.4 51.4 1.92 1.92
incl 51.7 65.5 13.8 13.5 2.21 2.21
incl 72.7 104.1 31.4 30.8 2.19 2.19
YM10-26 51.2 111.2 60.0 53.8 1.96 1.96
incl 51.2 77.8 26.6 23.9 2.73 2.73
YM10-28 60.5 65.0 4.5 3.7 3.30 3.30 Hole extended to test syenite

70.5 115.1 44.6 36.8 2.61 2.61
incl 77.4 108.5 31.1 25.5 3.15 3.15
YM11-29 72.01 109.2 37.19 33.3 5.37 5.37
YM11-31 52.65 55.65 3.0 3.0 3.08 3.08

70.83 105.8 34.97 34.9 3.72 3.67
113 117.0 4.0 4.0 1.54 1.54
YM11-39 81.9 95.0 13.1 11.9 14.68 7.31
incl 84.9 95.0 10.1 9.2 18.77 9.21
YR-12 34.1 71.0 36.9 35.9 3.59 3.59
YR-13 38.4 87.1 48.7 47.3 2.61 2.38
YR-14 61.0 117.1 56.1 44.9 4.85 4.85
YR-15 28.8 36.0 7.2 4.9 1.95 1.95
64.9 109.8 44.9 31.0 4.05 4.05
122.0 132.4 10.4 7.3 2.67 2.67
YR-16 47.0 101.8 54.8 45.9 5.32 5.32
YR-17 29.0 73.0 44.0 43.6 6.34 6.18
YR-25 34.5 45.7 11.2 9.2 4.73 4.73
64.2 101.5 37.3 30.7 3.18 3.18
YR-30 48.8 97.3 48.5 43.3 3.88 3.87
YR-31 39.1 77.6 38.5 38.5 3.99 3.99
YR-35 45.5 79.1 33.6 30.9 4.65 4.65
YR-36 61.0 105.0 44.0 37.0 11.13 5.06
YR-37 58.0 128.0 70.0 52.8 2.66 2.66
YR-38 37.0 46.9 9.9 9.4 11.39 5.84

62.0 72.0 10.0 9.5 9.65 7.83
YR-50 67.5 89.4 21.9 19.8 6.41 5.86

94.5 100.4 5.9 5.3 3.55 3.55



117.0 127.5 10.5 9.5 2.15 2.15

Figure 3 - UBZ Drill Section 23510

(Red lines are mineralized portions of the drill holes reported in Table 1.

Magenta shows the resource outline for the UBZ.

Red lines appearing outside of the resource outline represent new resource potential).

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig3.JPG

Figure 4 - UBZ Drill Section 23540

(Red lines are mineralized portions of the drill holes reported in Table 1.

Magenta shows the resource outline for the UBZ.

Red lines appearing outside of the resource outline represent new resource potential).

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig4.JPG

Figure 5 - UBZ Drill Sections 23570

(Red lines are mineralized portions of the drill holes reported in Table 1.

Magenta shows the resource outline for the UBZ.

Red lines appearing outside of the resource outline represent new resource potential).

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig5.JPG

Figure 6 - UBZ Drill Section 23600

(Red lines are mineralized portions of the drill holes reported in Table 1.

Magenta shows the resource outline for the UBZ.

Red lines appearing outside of the resource outline represent new resource potential).

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig6.JPG

Figure 7 - UBZ Drill Section 23630

(Red lines are mineralized portions of the drill holes reported in Table 1.

Magenta shows the resource outline for the UBZ.

Red lines appearing outside of the resource outline represent new resource potential).

www.northgateminerals.com/Theme/Northgate/files/Releases/2011/YDUBZFig7.JPG

Appendix 1: Complete Assay Results from UBZ Delineation Drill Program

Hole ID From
(m)
To
(m)
Interval
(m)
True Thickness
(m)
Gold Uncut
(g/t)
Gold Cut
20 g/t
Comment
YM10-04 39.5 44.0 4.5 4.4 3.19 3.19 Upper UBZ
YM10-05 No significant values
YM10-06 37.7 42.9 2.64 3.9 2.64 2.64 Upper UBZ
60.8 63.9 3.1 2.3 2.48 2.48 Upper UBZ
83.0 91.9 8.9 6.9 2.94 2.94 Upper UBZ
YM10-07 80.8 88 7.2 6.6 1.19 1.19 Upper UBZ
YM10-08 No significant values
YM10-09 No significant values
YM10-10 31.6



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