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Mineral Resources

Independent mineral resource estimates for the three deposits (Hangar Flats, West End and Yellow Pine) comprising the Golden Meadows Project in Valley County, Idaho, were prepared by SRK Consulting (Canada) Inc. ("SRK") in accordance with Canada's National Instrument 43-101. A summary of the mineral resource estimates is tabulated below, and the details of all three mineral resource estimates will be provided in a NI43-101 Technical Report to be filed in conjunction with the completion of a preliminary economic assessment in Q3/12. The substantial majority of these mineral resources are located on patented mineral claims.

Mineral Resource Estimate(1) - All Three Deposits comprising the Golden Meadows Project, Idaho

Prepared by SRK Consulting (Canada) Inc., June 25, 2012
Mineral Resource
Category
Tonnes
(000s)
Gold Grade
(g/t)
Contained Gold
(000s oz)
Silver Grade(5)
(g/t)
Contained Silver
(000s oz)
Antimony Grade(4)(5)
(%)
Contained Antimony (000s lbs)
Open Pit Oxide(2) Mineral Resources
Indicated 10,573 0.90 305 0.00 - 0.00% 122
Inferred 2,201 0.97 68 0.00 - 0.00% 178
Open Pit Sulphide(3) Mineral Resources
Indicated 67,653 1.80 3,925 0.60 1,312 0.07% 108,385
Inferred 53,917 1.63 2,822 0.93 1,603 0.08% 92,606
Total Open Pit Oxide + Sulphide(2)(3) Mineral Resources
Indicated 78,226 1.68 4,229 0.52 1,312 0.06% 108,507
Inferred 56,117 1.60 2,890 0.89 1,603 0.07% 92,784
  1. Mineral resources are reported in relation to a conceptual pit shell. Mineral resources are not mineral reserves and do not have demonstrated economic viability - see "Compliance with NI43-101" below. All figures are rounded to reflect the relative accuracy of the estimate. All composites have been capped where appropriate.
  2. Open pit oxide mineral resources are reported at a cut-off grade of 0.42 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below).
  3. Open pit sulfide mineral resources are reported at a cut-off grade of 0.75 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below).
  4. Where antimony grades are shown as "0.00" there is antimony present but it rounds to 0.00.
  5. Antimony and silver were not estimated for the West End deposit due to a lack of sufficient assays, and is averaged into the totals at an assumed zero grade.

Antimony Subdomains(1) Mineral Resource, Yellow Pine & Hangar Flats Deposits, Golden Meadows Project, Idaho

Prepared by SRK Consulting (Canada) Inc., June 25, 2012
Mineral Resource
Category
Tonnes
(000s)
Gold Grade
(g/t)
Contained Gold
(000s oz)
Silver Grade
(g/t)
Contained Silver
(000s oz)
Antimony Grade
(%)
Contained Antimony
(000s lbs)
Open Pit Sulphide(2) Mineral Resources
Indicated 9,999 2.31 743 3.15 1,012 0.49% 108,507
Inferred 8,639 2.08 576 5.04 1,400 0.49% 92,784
  1. Mineral resources are reported in relation to a conceptual pit shell. Mineral resources are not mineral reserves and do not have demonstrated economic viability - see "Compliance with NI43-101" below. All figures are rounded to reflect the relative accuracy of the estimate. All composites have been capped where appropriate.
  2. Open pit sulfide mineral resources are reported at a cut-off grade of 0.75 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below). The antimony subdomain is further limited to discrete zones of mineralization with grades that exceed 0.1% Sb.

Compliance with National Instrument 43-101

The technical information in this website has been prepared in accordance with Canadian regulatory requirements set out in National Instrument 43-101 and reviewed by Stephen P. Quin, P. Geo., President & CEO of Midas Gold Inc. Midas Gold's exploration activities at Golden Meadows were carried out under the supervision of Christopher Dail, C.P.G., Qualified Person and Project Manager.

Some of the mineral resources at Golden Meadows are categorized as indicated and some as inferred mineral resources. Mineral resources that are not mineral reserves do not have demonstrated economic viability. Mineral resource estimates do not account for mineability, selectivity, mining loss and dilution. These mineral resource estimates include 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 measured and indicated categories through further drilling, or into mineral reserves, once economic considerations are applied.

Cautionary Note - The mineral resource estimates referenced in this website use the terms "Indicated Mineral Resources" and "Inferred Mineral Resources." We advise you that while these terms are defined in and required by Canadian regulations, these terms are not defined terms under the U.S. Securities and Exchange Commission ("SEC") Industry Guide 7 and are normally not permitted to be used in reports and registration statements filed with the SEC. "Inferred Mineral Resources" have a great amount of uncertainty as to their existence, and great uncertainty as to their economic and legal feasibility. The SEC normally only permits issuers to report mineralization that does not constitute SEC Industry Guide 7 compliant "reserves" as in-place tonnage and grade without reference to unit measures. U.S. investors are cautioned not to assume that any part or all of mineral deposits in these categories will ever be converted into reserves. Midas Gold is not an SEC registered company.

The details of all three mineral resource estimates will be provided in a NI43-101 Technical Report to be filed in conjunction with the completion of a preliminary economic assessment due in Q3/12.

David Rowe, CPG, of SRK Consulting (Canada), Inc. is the qualified person, as defined in National Instrument 43-101, responsible for the mineral resource estimates for the Hangar Flats deposit as reported herein. He has read and approved the relevant technical portions of this news release related to the mineral resource estimates for which he is responsible.

Hangar Flats

The base case mineral resource estimate for the Hangar Flats deposit was prepared by SRK Consulting (Canada) Inc. and is summarized herein. The economically driven pit shell that limits the mineral resource was based entirely on gold value, with antimony and silver reporting within the resource-limiting pit but not defining it. Within the resource-limiting pit, antimony and silver grades are reported without any cut-off. Any mineralization lying outside the resource-limiting pit is not reported as mineral resources.

Since the date of this mineral resource estimate, additional drilling has been completed at Hangar Flats, and is continuing, that is extending the mineralization to the west and east beside and below the mineral resources reported herein, while Midas Gold plans to test possible extensions to the south of the current mineral resource later in 2012, subject to permitting, in areas where prior drilling has indicated potential for extensions to mineralization and is supported by airborne EM geophysical anomalies.

Mineral Resource Statement(1), Hangar Flats Deposit, Golden Meadows Project, Idaho

Prepared by SRK Consulting (Canada) Inc., June 25, 2012
Mineral Resource
Category
Tonnes
(000s)
Gold Grade
(g/t)
Contained Gold
(000s oz)
Silver Grade
(g/t)
Contained Silver
(000s oz)
Antimony Grade
(%)
Contained Antimony
(000s lbs)
Open Pit Oxide(2) Mineral Resources
Indicated 750 0.73 18 - - - -
Inferred 589 0.82 15 - - - -
Open Pit Sulphide(3) Mineral Resources
Indicated 16,440 1.73 914 1.37 725 0.12 44,217
Inferred 7,828 1.50 378 0.09 22 0.02 3,106
Total Open Pit Oxide + Sulphide(2)(3) Mineral Resources
Indicated 17,189 1.69 932 1.31 725 0.12 44,217
Inferred 8,416 1.45 393 0.08 22 0.02 3,106
  1. Mineral resources are reported in relation to a conceptual pit shell. Mineral resources are not mineral reserves and do not have demonstrated economic viability - see "Compliance with NI43-101" below. All figures are rounded to reflect the relative accuracy of the estimate. All composites have been capped where appropriate.
  2. Open pit oxide mineral resources are reported at a cut-off grade of 0.42 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below).
  3. Open pit sulfide mineral resources are reported at a cut-off grade of 0.75 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below).

Higher Grade Antimony Area at Hangar Flats

As noted above, within the larger envelope of gold mineralization, there are zones significantly enriched in antimony and silver relative to the overall mineral resource. These zones, defined by a plus 0.1% antimony shell, lie entirely within the pit-limited mineral resource and are reported separately below to illustrate the higher grades of antimony and silver within the overall mineral resource.

Mineral Resource Antimony Subdomain(1) , Hangar Flats Deposit, Golden Meadows Project, Idaho

Prepared by SRK Consulting (Canada) Inc., June 13, 2012
Mineral Resource Category Tonnes
(000s)
Gold Grade
(g/t)
Contained Gold
(000s oz)
Silver Grade
(g/t)
Contained Silver
(000s oz)
Antimony Grade
(%)
Contained Antimony
(000s lbs)
Open Pit Sulphide(2) Mineral Resources
Indicated 3,475 2.16 242 4.31 482 0.58 44,217
Inferred 339 1.33 14 0.91 10 0.42 3,106
  1. Mineral resources are reported in relation to a conceptual pit shell. Mineral resources are not mineral reserves and do not have demonstrated economic viability - see "Compliance with NI43-101" below. All figures are rounded to reflect the relative accuracy of the estimate. All composites have been capped where appropriate.
  2. Open pit sulfide mineral resources are reported at a cut-off grade of 0.75 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below). The antimony subdomain is further limited to discrete zones of mineralization with grades that exceed 0.1% Sb.

Mineral resource estimates for Hangar Flats were completed using Gemcom GEMS(r) software by David Rowe, C.P.G., of SRK Consulting (Canada), Inc. and incorporates the results of 49 holes drilled in 2011 and 2012 that were not utilized in the prior mineral resource estimate.

In reviewing the total drilling database, SRK and Midas Gold have eliminated all underground channel samples and any historic Bradley era holes that were not supported by Midas drilling, which resulted in a drop in total contained ounces of gold, especially from the inferred category. The underground channel samples were deemed inferior to the historic drilling, which holes were primarily drilled in the 1940's using typical 'A' gauge core bits, with sludge and core both assayed. While the channel samples may have identified mineralization, the quality of the samples and the lack of reliable mapping in reference to the samples preclude confident estimation into immediately adjacent areas. Additional drilling would be required to determine whether this data could be used (if verified) or replaced in future mineral resource estimates with new data. The veracity of the remaining historic drilling, which was completed in the 1940s through the 1990s, was confirmed through a rigorous data verification protocol. This included reviewing original drill logs, assay certificates and survey information, comparison of data from different drilling campaigns within the same area, and comparison to the Midas Gold holes. Blocks of 25m and 50m that were well informed (6 samples minimum) by both historic data and recent drilling were compared to validate the older data. Where no bias existed, and where good correlations dominated, the older data was used in grade estimation.

Three dimensional structural domains were constructed based on the orientation of the structural controls for gold deposition, and the gold deposit extents were limited within a gold shell constructed at a 0.25 g/t Au fire assay ("AuFA") threshold. The gold shell was also limited at the boundaries of the deposit so as not to extend more than 60 meters beyond any mineralized drill hole intercept. Antimony and silver shells were also constructed to drill holes, with 0.1% Sb and 5 g/t Ag cut-offs. Although spatially related, the antimony and silver mineralization is characterized by different structural controls than the gold mineralization.

Original gold, silver, and antimony assay values from drilling were capped, according to cumulative frequency plots of assays within resource limiting shells. Gold capping of individual assays resulted in a loss of 4% total metal. For silver and antimony, capping resulted in metal losses of 10% and 12% respectively. Composite samples were then created at three meter intervals, and were restricted to the limits of the 0.25g/t Au shell.

Ordinary kriging was used to interpolate grades within each of the three structural domains, and the total gold, silver, and antimony block model estimates consisted of two successively larger passes. The first pass used a maximum search radius of 40, 50, and 45 meters for each gold, silver, and antimony respectively, which represents one half (1/2) of the maximum range of the variography, and was subdivided into octants for gold only. The second pass was set to estimate the remaining blocks within the gold shell. Total gold, silver, and antimony assay values were estimated within blocks measuring 15x15x6 meters.

Once the estimation process was completed, the previously mined areas were removed, based on available surveys of the existing underground workings, the limits of which have been locally confirmed by holes drilled through voids and timbers.

Mineral resources are classified in the Indicated category for all blocks estimated by at least four composite samples from a minimum of two drill holes, and a minimum of three octants from the first interpolation pass which searched out to 40 metres or one half (1/2) of the maximum range of sample grade continuity defined by the variography. Final broad areas of indicated blocks were outlined by constructing a classification envelope designed to encompass zones predominantly flagged by the first search pass. This process allows review of the geologic control/confidence on the deposit, and expands certain areas but excludes others from Indicated category. All remaining blocks within the gold shell are classified as Inferred.

West End

The base case mineral resource estimate for the West End deposit as prepared by SRK Consulting (Canada) Inc. is summarized below.

Mineral Resource Statement (1) , West End Deposit, Golden Meadows Project, Idaho

Prepared by SRK Consulting (Canada) Inc., May 11, 2012
Mineral Resource Category Tonnes
(000s)
Gold Grade
(g/t)
Contained Gold
(000s oz)
Open Pit Oxide(2) Mineral Resources
Indicated 8,251 0.83 221.1
Inferred 1,185 0.63 23.9
Open Pit Sulphide(3) Mineral Resources
Indicated 25,750 1.52 1,262.3
Inferred 14,076 1.30 588.1
  1. Mineral resources are reported in relation to a conceptual pit shell. Mineral resources are not mineral reserves and do not have demonstrated economic viability - see "Compliance with NI43-101" below. All figures are rounded to reflect the relative accuracy of the estimate. All composites have been capped where appropriate.
  2. Open pit oxide mineral resources are reported at a cut-off grade of 0.42 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below).
  3. Open pit sulfide mineral resources are reported at a cut-off grade of 0.75 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below).

Mineral resource estimates for West End were completed using Gemcom GEMS(r) software by David Rowe, C.P.G., of SRK Consulting (Canada), Inc. and incorporates the results of 21 holes drilled in 2010 and 2011 that were not utilized in the prior mineral resource estimate, as well as a more robust approach to handling the oxide vs. sulphide boundary. These holes were primarily drilled to test the potential to expand the boundaries of the West End mineral resource below, and to the west and east of the previous estimate. These holes also assisted with confirming prior resource estimates since the holes were generally started off within the existing mineral resource and penetrated through it before extending outside the prior resource limits.

This resource estimate relies on an extensive database of 655 holes drilled by owners prior to Midas Gold and was supplemented by the 21 holes completed by Midas Gold. The veracity of the historic drilling, which was completed in the 1970s through the 1990s, was confirmed through a rigorous data verification protocol. This included reviewing original drill logs, assay certificates and survey information, comparison of data from different drilling campaigns within the same area, and production reconciliation records from mining operations (including a review by the former chief geologist that supervised much of the drilling and the mining operations for a period in the early 1990s), and comparison to the Midas Gold holes. The verification process resulted in a high degree of confidence in the quality of drilling prior to Midas Gold's drilling and is detailed in the June 2011 Technical Report, a copy of which is filed on SEDAR.

Three dimensional geologic domains were constructed based on host rock lithologies, and the gold deposit extents were limited within a gold shell constructed at a 0.25 g/t Au fire assay ("AuFA") threshold. The gold shell was also limited at the boundaries of the deposit so as not to extend more than 50 meters beyond any mineralized drill hole intercept.

The geologic model was further subdivided into three distinct regions for resource estimation based on the orientation of the structural controls for gold deposition. Original drill hole gold fire assay values were capped within each lithologic domain to restrict the influence of high grade outlier values. Composite samples were then created at three meter intervals, and were restricted to the limits of the host lithologic domain; composites from one lithologic domain were not used in interpolation of blocks in a different lithologic domain.

Separate interpolation passes using ordinary kriging were utilized within each of the three structural regions, and the total gold block model estimate consisted of two successively larger passes. The first pass used a maximum search radius of 45 meters, which represents one half (1/2) of the maximum range of the variography, and was subdivided into octants. The second pass was set to estimate the remaining blocks within the gold shell. Total gold from fire assay values were estimated within blocks measuring 15x15x6 meters. A separate gold model was also estimated using only cyanide leachable gold composite values ("AuCN"). Oxide gold mineralization was outlined by calculating the ratio of the cyanide leachable gold block values by the total gold block values (AuCN/AuFA). Only blocks with AuCN/AuFA ratio values greater than 0.7 were included in the final oxide resource. All other blocks were reported as sulphide resource.

Once the estimation process was completed, the previously mined areas were removed, based on available surveys of the existing open pits, the limits of which have been locally confirmed by holes drilled through backfill material that was placed in some of the pits post-mining, where applicable.

Resources are classified in the Indicated category for all blocks estimated by at least four composite samples from a minimum of two drill holes, and a minimum of two octants from the first interpolation pass which searched out to 45 metres or one half (1/2) of the maximum range of sample grade continuity defined by the variography. All remaining blocks within the gold shell are classified as Inferred.

Yellow Pine

Mineral Resource Statement (1) , Yellow Pine Deposit, Golden Meadows Project, Idaho

Prepared by SRK Consulting (Canada) Inc., May 31, 2012
Mineral Resource Category Tonnes
(000s)
Gold Grade
(g/t)
Contained Gold
(000s oz)
Silver Grade
(g/t)
Contained Silver
(000s oz)
Antimony Grade (4)
(%)
Contained Antimony
(000s lbs)
Open Pit Oxide(2) Mineral Resources
Indicated 1,572 1.30 66 - - 0.00 122
Inferred 427 2.12 29 - - 0.02 178
Open Pit Sulphide(3) Mineral Resources
Indicated 25,463 2.14 1,749 0.72 587 0.11 64,168
Inferred 32,013 1.80 1,856 1.54 1,581 0.13 89,500
Total Open Pit Oxide + Sulphide(2)(3) Mineral Resources
Indicated 27,036 2.09 1,814 0.68 587 0.11 64,290
Inferred 32,440 1.81 1,885 1.52 1,581 0.13 89,678
  1. Mineral resources are reported in relation to a conceptual pit shell. Mineral resources are not mineral reserves and do not have demonstrated economic viability - see "Compliance with NI43-101" below. All figures are rounded to reflect the relative accuracy of the estimate and therefore numbers may not appear to add precisely. All composites have been capped where appropriate.
  2. Open pit oxide mineral resources are reported at a cut-off grade of 0.42 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below).
  3. Open pit sulfide mineral resources are reported at a cut-off grade of 0.75 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below).
  4. Where antimony grades are shown as "0.00" there is antimony present but it rounds to 0.00.

The base case mineral resource estimate for the Yellow Pine deposit as prepared by SRK Consulting (Canada) Inc. and is summarized herein. Sensitivity according to gold cut-off grade is summarized below. The economically driven pit shell that limits the mineral resource was based entirely on gold value, with antimony and silver reporting within the resource-limiting pit but not defining it. Within the resource-limiting pit, antimony and silver grades are reported without any cut-off. Any mineralization lying outside the resource-limiting pit is not reported as mineral resources.

Since the date of this mineral resource estimate, additional drilling has been completed, and is continuing, that is extending the mineralization to the west and east beside and below the mineral resources reported herein, while Midas Gold plans to test possible extensions to the south of the current mineral resource later in 2012, subject to permitting, in areas where prior drilling has indicated potential for extensions to mineralization.

Higher Grade Antimony Area

As noted above, within the larger envelope of gold mineralization, there are zones significantly enriched in antimony and silver relative to the overall mineral resource. These zones, defined by a plus 0.1% antimony shell, lie entirely within the pit-limited mineral resource and are reported separately below to illustrate the higher grades of antimony and silver within the overall mineral resource.

Mineral Resource Antimony Subdomain(1) , Yellow Pine Deposit, Golden Meadows Project, Idaho

Prepared by SRK Consulting (Canada) Inc., May 31, 2012
Mineral Resource
Category
Tonnes
(000s)
Gold Grade
(g/t)
Contained Gold
(000s oz)
Silver Grade
(g/t)
Contained Silver
(000s oz)
Antimony Grade
(%)
Contained Antimony
(000s lbs)
Open Pit Sulphide(2) Mineral Resources - Antimony Subdomain
Indicated 6,524  2.39 501  2.53 530  0.45 64,290
Inferred 8,300  2.11 562  5.21 1,390  0.49 89,678
  1. Mineral resources are reported as a subset of the total mineral resource in relation to a conceptual pit shell. Mineral resources are not mineral reserves and do not have demonstrated economic viability - see "Compliance with NI43-101" below. All figures are rounded to reflect the relative accuracy of the estimate. All composites have been capped where appropriate.
  2. Open pit sulfide mineral resources are reported at a cut-off grade of 0.75 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below). The antimony subdomain is further limited to discrete zones of mineralization with grades that exceed 0.1% Sb.

Geographic Distribution of Mineral Resources

For ease of reference to prior news releases detailing results of drilling, the mineral resource estimate within the pit shell is also provided below, split into a south area (around the former Yellow Pine open pit operated by Bradley Mining in the 1930s through 1950s), and a north area (around and below the old Clark Tunnel and Homestake area (Hecla Mining Company operated a small scale open pit heap leach operation on oxide material in the Homestake area in the 1990s). The southern portion of the mineral resources tends to have slightly higher gold but significantly higher antimony and silver grades than the northern portion of the deposit.

Mineral Resource Statement (1) , Yellow Pine Deposit - South Area, Golden Meadows Project, Idaho

Prepared by SRK Consulting (Canada) Inc., May 31, 2012
Mineral Resource Category Tonnes
(000s)
Gold Grade
(g/t)
Contained Gold
(000s oz)
Silver Grade
(g/t)
Contained Silver
(000s oz)
Antimony Grade
(%)
Contained Antimony
(000s lbs)
Open Pit Oxide(2) Mineral Resources - South Area
Indicated 762 1.34 33 0.00 0.00 0.01 100
Inferred 252 2.65 21 0.00 0.00 0.03 150
Open Pit Sulphide(3) Mineral Resources - South Area
Indicated 17,953 2.23 1,288 0.76 439 0.13 51,751
Inferred 25,454 1.79 1,465 1.90 1,555 0.15 86,733
  1. Mineral resources are reported in relation to a conceptual pit shell. Mineral resources are not mineral reserves and do not have demonstrated economic viability - see "Compliance with NI43-101" below. All figures are rounded to reflect the relative accuracy of the estimate. All composites have been capped where appropriate.
  2. Open pit oxide mineral resources are reported at a cut-off grade of 0.42 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below).
  3. Open pit sulfide mineral resources are reported at a cut-off grade of 0.75 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below).

Mineral Resource Statement (1), Yellow Pine Deposit - North Area, Golden Meadows Project, Idaho

Prepared by SRK Consulting (Canada) Inc., May 31, 2012
Mineral Resource Category Tonnes
(000s)
Gold Grade
(g/t)
Contained Gold
(000s oz)
Silver Grade
(g/t)
Contained Silver
(000s oz)
Antimony Grade
(%)
Contained Antimony
(000s lbs)
Open Pit Oxide(2) Mineral Resources - North Area
Indicated 810 1.26 33 0.00 0.00 0.00 21
Inferred 174 1.36 8 0.00 0.00 0.01 28
Open Pit Sulphide(3) Mineral Resources - North Area
Indicated 7,510 1.91 461 0.61 148 0.07 12,418
Inferred 6,559 1.86 391 0.12 26 0.02 2,767
  1. Mineral resources are reported in relation to a conceptual pit shell. Mineral resources are not mineral reserves and do not have demonstrated economic viability - see "Compliance with NI43-101" below. All figures are rounded to reflect the relative accuracy of the estimate. All composites have been capped where appropriate.
  2. Open pit oxide mineral resources are reported at a cut-off grade of 0.42 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below).
  3. Open pit sulfide mineral resources are reported at a cut-off grade of 0.75 g/t Au. Cut-off grades are based on a price of US$1,400 per ounce of gold and a number of operating cost and recovery assumptions, plus a 15% contingency (see details below).
  4. Where antimony grades are shown as "0.00" there is antimony present but it rounds to 0.00.

Mineral resource estimates for Yellow Pine were completed using Gemcom GEMS(r) software by David Rowe, C.P.G., of SRK Consulting (Canada), Inc. and incorporates the results of 92 holes drilled in 2011 and 2012 that were not utilized in the prior mineral resource estimate.

This resource estimate relies on an extensive database of 451 holes drilled by owners prior to Midas Gold, and on 92 holes completed by Midas Gold. In reviewing the total drilling database, SRK and Midas Gold have eliminated 215 drill holes of the total 758 drilled from consideration for various quality assurance reasons. These 215 eliminated holes were primarily drilled in the 1940's using typical 'A' gauge core bits, with sludge and core both assayed and, while they may have identified mineralization, these areas that have not already been delineated by later drilling, will need to be re-drilled prior to incorporating them into a mineral resource estimate. Where the original assay intervals were composited, these holes were removed from consideration. Shallow churn drill holes and air track drill holes were also excluded from the resource calculation. The veracity of the remaining historic drilling, which was completed in the 1940s through the 1990s, was confirmed through a rigorous data verification protocol. This included reviewing original drill logs, assay certificates and survey information, comparison of data from different drilling campaigns within the same area, and comparison to the Midas Gold holes. Blocks of 25m and 50m that were well informed (6 samples minimum) by both historic data and recent drilling were compared to validate the older data. Where no bias existed, and where good correlations dominated, the older data was used in grade estimation. The verification process has increased the degree of confidence in the quality of drilling prior to Midas Gold's ownership.

Three dimensional structural domains were constructed based on the orientation of the structural controls for gold deposition, and the gold deposit extents were limited within a gold shell constructed at a 0.25 g/t Au fire assay ("AuFA") threshold. The gold shell was also limited at the boundaries of the deposit so as not to extend more than 60 meters beyond any mineralized drill hole intercept. Antimony and silver shells were also constructed, at 0.1% Sb and 10 g/t Ag respectively. Although spatially related, the antimony and silver mineralization is characterized by different structural controls than the gold mineralization.

Original drill hole gold, silver, and antimony assay values were capped, at 13.5 g/t, 100 g/t, and 7.0% respectively, within the gold grade shell to restrict the influence of high grade outlier values. Composite samples were then created at three meter intervals, and were restricted to the limits of the 0.25g/t Au shell.

Ordinary kriging was used to interpolate grades within each of the three structural domains, and the total gold, silver, and antimony block model estimates consisted of two successively larger passes. The first pass used a maximum search radius of 45 meters for each gold, silver, and antimony, which represents one half (1/2) of the maximum range of the variography, and was subdivided into octants for gold only. The second pass was set to estimate the remaining blocks within the gold shell. Total gold, silver, and antimony assay values were estimated within blocks measuring 15x15x6 meters.

Once the estimation process was completed, the previously mined areas were removed, based on available surveys of the existing open pits, the limits of which have been locally confirmed by holes drilled through backfill material that was placed in some of the pits post-mining, where applicable.

Mineral resources are classified in the Indicated category for all blocks estimated by at least four composite samples from a minimum of two drill holes, and a minimum of three octants from the first interpolation pass which searched out to 45 metres or one half (1/2) of the maximum range of sample grade continuity defined by the variography. Final broad areas of indicated blocks were outlined by constructing a classification envelope designed to encompass zones predominantly flagged by the first search pass. This process allows review of the geologic control/confidence on the deposit, and expands certain areas but excludes others from Indicated category. All remaining blocks within the gold shell are classified as Inferred.