Nighthawk Reports 45.3% Increase in Contained Gold Ounces and 59% Increase in Average Grade in Updated Colomac Resource Estimate of 2.1 Million Ounces Gold Inferred at an Average Grade of 1.67 g/t Gold

Toronto, Ontario, June 17, 2013– Nighthawk Gold Corp. (“Nighthawk“) (TSX Venture: NHK) is pleased to report an updated Inferred Mineral Resource estimate, prepared in accordance with National Instrument 43-101, (“NI 43-101”), of 39.815 million tonnes with an average grade of 1.67 grams per tonne gold for 2.101 million ounces gold using a cut-off grade of 0.6 g/t gold (see Table 1) at its 100%-owned Colomac gold property in the Northwest Territories.


  • The average grade of the current resource increased by 59% and total contained ounces increased by 45.3% over the previous Inferred Mineral Resource estimate of 42.650 million tonnes with an average grade of 1.05 g/t gold for 1.446 million ounces gold using a cut-off grade of 0.6 g/t gold. (February 22, 2012 news release);
  • Grade sensitivity tables show that a significant number of ounces are present even when cut-off grades are increased.  By increasing the cut-off from 0.60 g/t gold to 1.0 g/t gold the average grade increases to 1.95 g/t gold resulting in a total of 1.835 million ounces gold, and by increasing the cut-off grade to 1.50 g/t gold the average grade increases to 2.45 g/t gold resulting in a total of 1.340 million ounces gold (see Table 2);
  • Colomac’s five known gold deposits (Fig. 1) outlined in this reporting include: Colomac Sill, Goldcrest North, Goldcrest South, Grizzly Bear, and 24-27, of which the Colomac Sill currently accounts for 93.5% of the resource. All deposits are open laterally and to depth (see Fig. 1);
  • Nighthawk’s 2012 drilling tested portions of a 2.5 kilometre section of the 5.5 kilometre sill outlined in the resource. This section contains 30.010 million tonnes at an average grade of 1.75 g/t gold for a total of 1.687 million ounces gold, representing only 40% of the sill’s potential mineralized length to a depth of 450 metres;
  • A steeply plunging higher grade shoot at Zone 3.5 (Figs. 2a, 2b), located within the southern portion of the sill, contains 0.528 million ounces gold at 2.15 g/t gold.  Similar shoots have been identified over the seven kilometre length of the sill that require further drilling; and
  • Goldcrest Sill, 400 metres west of the Colomac Sill, has the highest average grade (2.2 g/t gold) and represents a high priority target for resource growth given its grade and limited shallow historic drilling (generally less than 100 metres depth).

“The increase in the resource estimate’s contained ounces well exceeded our expectations and the average grade is now in line with the former head grade at the past producing Colomac Mine. More than 60% of the Colomac sill’s historically defined near surface gold zones remain untested by Nighthawk and the other four satellite deposits represented in the resource update have significant exploration upside potential as well,” said David Wiley, President and CEO of Nighthawk Gold. “In addition to the unexplored opportunities at Colomac, the balance of our 222,203 acre property package hosts numerous gold deposits and showings, illustrating the area’s vast potential beyond Colomac. The updated resource estimate at Colomac represents an inflection point for the company. We look forward to reporting our progress as we continue to grow and develop the project.”

Table 1 – Colomac Gold Project Inferred Mineral Resources by Zone

 Using Block Model Cut-off Grade of 0.6 g/t gold, up to 450 metres depth



g/t gold

Oz gold

Colomac North




Colomac Central




Colomac South




Goldcrest North




Goldcrest South




Grizzly Bear

















  1. A block cut-off value of 0.6 g/t gold was applied to all resource blocks.
  2. Tonnes and ounces have been rounded to reflect the relative accuracy of the mineral resource estimate; therefore, numbers may not total correctly.
  3. Mineral Resources were calculated with Micromine mining software. Drill holes traces showing lithology and gold grade were reviewed in plan and cross section. Colomac and Goldcrest geological domains were created using Leapfrog Implicit Geological Modeling Software. Assays within each domain were top cut to 31 g/t and then composited to regular 1.5 metre intervals.  Block model grade interpolation was undertaken using Ordinary Kriging (OK).
  4.  The estimation methodology and results for the Grizzly Bear, 27 and 24 zones is the same as reported in 2012.
  5. The resource estimate was prepared by Leon McGarry, B.Sc., Geologist, ACA Howe.
  6. A default average specific gravity (SG) value of 2.7 has been used.
  7. Mineral resource tonnes quoted are not diluted.
  8. No Measured or Indicated Resources or Mineral Reserves of any category are identified.  
  9. Mineral resources are not mineral reserves and by definition do not demonstrate economic viability. This mineral resource estimate includes Inferred Mineral Resources that are normally considered too speculative geologically to have economic considerations applied to them that would enable them to be categorized as mineral reserves. There is also no certainty that these Inferred Mineral Resources will be converted to the measured and indicated resource categories through further drilling, or into mineral reserves, once economic considerations are applied.

Table 2 – Colomac Gold Project Global Block Model Cut-off Grade Sensitivity Table

Block Model Cut-off Value g/t

Block Model Tonnage

Block Model Avg. Grade g/t gold

Total Oz gold





























Note: The reader is cautioned that the figures in this table are not a Mineral Resource Statement. The figures are only presented to show the sensitivity of the block model estimates to the selection of cut-off grade.


2013 Resource Estimate

The mineral resource estimate was prepared in accordance with NI 43-101. Gold zones are characterized by significant mineralized widths representing near-surface bulk tonnage deposits. Resources were defined using a block cut-off grade of 0.6 g/t gold. The 2013 Resource Estimate utilizes historic diamond drilling results from approximately 916 holes, with 30 holes drilled during Nighthawk’s 2012 program and the balance of which were completed between 1987 and 1997. All resources have been assigned to the Inferred category due to the historic nature of the data and the need for additional verification work. Mined volumes of the Colomac Sill have been deleted from the current resource model. 

Mineralized Zones

Zone 2.0 hosts a well-defined mineralized shoot with true widths ranging from 40 metres near surface to 80 metres at depth (see Fig. 2a).  Steeply plunging to the northeast, this style of mineralization constitutes a key opportunity as recent drilling has confirmed its continuation and increasing widths with depth.  Zone 3.5, similar to Zone 2.0 but with significantly less drilling, has near surface true widths of 20 metres ranging to 40 metres at depth (see Fig. 2a).  The continuity and widths of mineralization characterizing these two zones establishes them as important prospects for resource expansion.  Although less well defined than Zone 2.0, Zone 3.5 contains 0.528 million ounces gold at 2.15 g/t gold, or over 1/4 of the current global resource with approximately 20% higher grade. Of the sill’s 7.0 kilometre strike length, 5.5 kilometres are outlined in the current estimate.  Since Zones 2.0 and 3.5 account for only about 20% of that mineralized length, the potential for the intrusion to host similar higher grade shoots exists and represents a significant opportunity. 

The Goldcrest Sill lies parallel to and 400 metres west of the compositionally similar Colomac Sill.   Two zones, Goldcrest North and South, lie along the sill’s 2.5 kilometre length and are included in the current resource.  Zone estimates are based exclusively on limited historic drilling generally to less than 100 metres depth.   The Goldcrest resource, having the highest average grade at 2.2 g/t gold, represents a primary underexplored target that is open laterally and to depth.

Figure 1: Plan View of Deposits at Colomac 

2013-06-17 - Plan View of Deposits at Colomac

Figures 2a – Contoured True Width of Mineralization & 2b – True Width x Grade (Metal Factor) 

2013-06-17 - Figures 2a – Contoured True Width of Mineralization & 2b – True Width x Grade

About The Colomac Gold Project

The Colomac Gold Project lies within the central portion of Nighthawk’s Indin Lake Gold Property, 220 kilometres northwest of Yellowknife, Northwest Territories. Access is by winter road from Yellowknife or year round by chartered aircraft to a 5,000 foot airstrip at the former Colomac Gold Mine site. Nighthawk has secured a contiguous land position fully surrounding the Colomac Gold Project by consolidating more than 90% of the Indin Lake Greenstone Belt including the related Indin Lake Gold Camp. The Colomac Gold Project contains at least five separate gold deposits open in all dimensions (Colomac Sill, Grizzly Bear, Goldcrest North, Goldcrest South, and 24/27), only one of which, the Colomac Sill Deposit, was historically mined. Intermittent mining from 1990 to 1997 was limited to three shallow open pits developed on a steeply dipping differentiated mafic intrusion (Colomac Sill). Historical production is reported to be 527,908 ounces gold with an average head grade of 1.66 g/t gold. Mining activities impacted only a small portion of the sill’s 7 kilometre mineralized strike length. All mining and processing equipment and infrastructure have been removed from the Colomac Property.

About Nighthawk Gold Corp.

Nighthawk is a Canadian-based exploration company focused on acquiring and developing gold mineral properties in the Northwest Territories. Its primary land position covers 222,203 acres or 900 square kilometres in the Indin Lake Gold Camp and includes an Inferred Mineral Resource estimate of 39.815 million tonnes with an average grade of 1.67 g/t gold for 2.101 million ounces gold using a cut-off grade of 0.6 g/t gold.

The technical aspects of this press release have been reviewed by Michael Byron, Ph.D., P.Geo., Chief Geologist and Director for Nighthawk, who is the “Qualified Person” as defined by NI 43-101 for this project.

Technical information related to the mineral resource estimate contained in this news release has been reviewed and approved by Ian Trinder, M.Sc., a Senior Geologist with A.C.A. Howe International Limited, who is an independent Qualified Person as defined by NI 43-101, with the ability and authority to verify the authenticity and validity of this data. The technical report supporting the mineral resource estimate will be filed on SEDAR within 45 days.

An Inferred Mineral Resource as defined by the CIM Standing Committee is “that part of a Mineral Resource for which quantity and grade or quality can be estimated on the basis of geological evidence and limited sampling and reasonably assumed, but not verified, geological and grade continuity. The estimate is based on limited information and sampling gathered through appropriate techniques from locations such as outcrops, trenches, pits, working and drill holes.”

Forward-Looking Statements

Certain information set forth in this news release may contain forward-looking statements that involve substantial known and unknown risks and uncertainties, including, but not limited to, the timing of future drilling, the expansion of the mineralization, and the remediation of historic reclamation sites. These forward-looking statements are subject to numerous risks and uncertainties, certain of which are beyond the control of Nighthawk, including, but not limited to, the impact of general economic conditions, industry conditions, volatility of commodity prices, risks associated with the uncertainty of exploration results and estimates, currency fluctuations, dependency upon regulatory approvals, the uncertainty of obtaining additional financing and exploration risk. Readers are cautioned that the assumptions used in the preparation of such information, although considered reasonable at the time of preparation, may prove to be imprecise and, as such, undue reliance should not be placed on forward-looking statements. This press release is not, and is not to be construed in any way as, an offer to buy or sell securities in the United States.

For more information about the Company, please visit

Neither the 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.

For more information, please contact:

David Wiley

President and CEO

Daniel Boase

Investor Relations

Nighthawk Gold Corp. First Canadian Capital Corp.
(647) 260-1247 (416) 742-5600 ext 232
(416) 363-4567 (FAX) Email:
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