Northgate Minerals Corporation

Notes

Note to US Investors:

This Annual Report uses the terms “measured”, “indicated” and “inferred” resources. United States investors are advised that while such terms are recognized and required by Canadian regulators, the SEC does not recognize them. Inferred resources have a great amount of uncertainty as to their existence, and as to their economic and legal feasibility. It cannot be assumed that all or any part of an inferred resource will ever be upgraded to a higher category. Under Canadian rules, estimates of inferred resources may not form the basis of feasibility or other economic studies. United States investors are cautioned not to assume that all or any part of measured or indicated resources will ever be converted into mineral reserves. United States investors are also cautioned not to assume that all or any part of an inferred resource exists, or is economically or legally mineable.

Note to Reserves and Resources

  1. The terms “Mineral Reserve”, “Proven Mineral Reserve” and “Probable Mineral Reserve” used in this report are Canadian mining terms as 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 (the “CIM”) Standards on Mineral Resources and Mineral Reserves Defi nitions and Guidelines adopted by the CIM Council on August 20, 2000. The terms “Mineral Resource”, “Measured Mineral Resource”, “Indicated Mineral Resource”, and “Inferred Mineral Resource” used in this report are Canadian mining terms as defined in accordance with National Instrument 43-101 Standards of Disclosure for Mineral Projects under the guidelines set out in the CIM Standards. Mineral reserves and mineral resources for Kemess South have been estimated in accordance with the defi nitions contained in the Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Standards and National Instrument 43-101.
  2. Mineral reserves for Fosterville and Stawell have been estimated in accordance with the AusIMM JORC Code and have been reconciled to CIM Standards as prescribed by National Instrument 43-101.
  3. All mineral resources are exclusive of mineral reserves.
  4. Mineral resources that are not mineral reserves do not have demonstrated economic viability.
  5. Mineral reserves and resources are rounded to 1,000 tonnes, 0.01 g/t gold and 1,000 ounces. Minor discrepancies in summations may occur due to rounding.
  6. Mineral reserves were calculated using the following parameters:
    • Kemess South: exchange rate Cdn$/US$1.20; gold price $675/oz; hedged copper price $2.52/lb; unhedged copper price $1.50/lb; and silver price $12.00/oz. Operating assumptions for the west pit were as follows: Gold recovery 66.1%; Copper recovery 82.4%; mining costs Cdn$1.80/tonne; milling costs Cdn$4.09/tonne; and G&A costs Cdn$1.57/tonne. For the east pit, operating assumptions were as follows: gold recovery 52.5%; copper recovery 70.8%; mining costs Cdn$1.20/tonne; milling costs Cdn$3.94/tonne; and, G&A costs Cdn$1.37/tonne.
    • Fosterville: exchange rate A$/US$0.70; gold price $675/oz; cut-off grade applied was variable for underground ore depending on width, mining method and ground conditions; dilution of 10%-20% and mining recovery of 70%-100% were applied depending on mining method.
    • Stawell: exchange rate A$/US$0.70; gold price $675/oz for the Magdala 1040RL extraction level; gold price $595/oz for all other under-ground reserves; cut-off grade applied was variable for underground ore depending upon width, mining method and ground conditions. Dilution of 2m–3m and mining recovery of 95%–100% were applied to the underground reserves, dependent upon mining method.
  7. Mineral resources were calculated using the following economic parameters:
    • Kemess South: exchange rate Cdn$/US$1.20; gold price $750/oz; copper price $2.00/lb.
    • Kemess North (mineral reserves now reclassifi ed as mineral resources following the decision of the BC government to deny Northgate the requisite development permit) calculated at the time of the feasibility study: exchange rate Cdn$/US$1.40; gold price $375/oz; copper price $1.00/lb; and, silver price $5.00/oz. Resources for Kemess North, calculated at the time of the feasibility study: exchange rate Cdn$/US$1.40; gold price $425/oz; copper price $1.20/lb; and silver price $5.00/oz.
    • Fosterville: exchange rate A$/US$0.70; gold price $750/oz; cut-off grade applied were 0.5 g/t gold for oxide, 1.0 g/t gold for near-surface sulphide (above 5050mRL <100m from surface) and 3.0 g/t gold for underground sulphide (below 5050mRL >100m from surface).
    • Stawell: exchange rate US$/A$0.70; gold price $750/oz for the mid-Magdala and C7 dukes extension areas; gold price $595/oz for all other areas. Magdala surface above 130mRL and above a nominal 0.8g/t Au cut-off; Wonga surface within a $595/oz optimised pit shell.
    • Young-Davidson: gold price $750/oz; assays are cut to 20 g/t gold and 20 g/t silver for all zones; underground mineralized wireframes constructed based on approximately a 1.70 g/t gold cut-off grade, and a 1.3 g/t incremental cut-off grade and a minimum true thickness of 3m; open pit mineralized wireframes constructed based on approximately a 0.60 g/t gold cut-off grade, and a minimum true thickness 5m; resources are reported at a 2.3 internal cut-off grade; underground blocks are 15m by 15m by 7m wide while open pit blocks are 5m by 5m by 5m. Both block models have a percent mineralization fi eld; 3.0m equal length composites created within the mineralized wireframes; inverse distance squared grade interpolation; standard search radii lengths and orientations employed for each mineralized lens; a 2.69 specific gravity was used; Maptek’s Vulcan® 7.5 software was used.
  8. Mineral reserve estimates were prepared by:
    • Kemess South: Gordon Skrecky, Chief Mine Geologist, Kemess mine. Mr. Skrecky is a member of the Association of Professional Engineers and Geoscientists of British Columbia and has over 22 years of experience in mineral resource estimation.
    • Fosterville: Roddy Ormonde, Mine Technical Superintendent, Northgate and Marcus Binks, Processing Manager, Northgate. Mr Ormonde is a member of the Australasian Institute of Mining and Metallurgy and has over 16 years of relevant engineering experience. Mr Binks is a member of the Australasian Institute of Mining and Metallurgy and has over 15 years of relevant metallurgical experience.
    • Stawell: Glenn Miller, Mine Technical Superintendent, Northgate. Mr. Miller is a member of the Australasian Institute of Mining and Metallurgy and has over 17 years of relevant engineering experience.
  9. Mineral resource estimates were prepared by:
    • Kemess North, including the Nugget Zone, (now all classifi ed as resources): Jim Gray of GR Technical Services Ltd. and Carl Edmunds, Exploration Manager, Northgate. Mr. Gray is a member of the Association of Professional Engineers and Geoscientists of the province of British Columbia, the Association of Professional Engineers, Geologists and Geophysicists of Alberta and the Canadian Institute of Mining and Metallurgy and has over 30 years of relevant engineering experience. Mr. Edmunds is a member of the Association of Professional Engineers, Geologists and Geophysicists of British Columbia and has 21 years of experience in mineral resource estimation.
    • Fosterville: Ian Holland, Production Manager, Northgate and Simon Hitchman, District Exploration Geologist, Northgate. Mr Holland is a member of the Australasian Institute of Mining and Metallurgy and has over 13 years of relevant geological experience. Mr Hitchman is a member of the Australasian Institute of Mining and Metallurgy and the Australian Institute of Geoscientists and has over 21 years of relevant geological experience.
    • Stawell: Mark Haydon, Geology Manager, Northgate, who is a member of the Australasian Institute of Geoscientists and has over 15 years of relevant geological experience.
    • Young-Davidson: Carl Edmunds, Exploration Manager, Northgate.

Back to Top