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Homestake Ridge Project - Significant Neighbouring Deposits in Northwest BC

Advanced Exploration Stage Gold and Silver Enriched VMS and Epithermal Project with a Defined 43-101 Compliant Resource

The Homestake Ridge Project is favourably located within the Iskut-Stewart-Kitsault Belt approximately 32km north-northwest of the tidewater communities of Alice Arm and Kitsault, BC, with road access within six kilometres. The Homestake Ridge property comprises 26 mineral claims containing 151 units and seven crown grants for a total area of 2,585 ha in the Skeena Mining Division with specific claims subject to a 2% net smelter return (NSR).

Figure 1 - Location of the Homestake Ridge Project, NW BC
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Infrastructure Highlights:

  • Superior access
  • 32km to tidewater at Alice Arm by historic roadway
  • Road access to within 6km of property
  • Synergies with  proposed hydro-development projects and existing infrastructure

Exploration on the property has identified two major accumulations of gold and silver mineralization of potential economic significance, known as the Main Homestake and Homestake Silver deposits. Mineralization is hosted within a complex sequence of lower to middle Jurassic sedimentary, volcanic and intrusive rocks of the Hazelton Group which, elsewhere in the Iskut-Stewart-Kitsault Belt have hosted multiple past producing mines, (each producing >1million oz gold) and other major mineral deposits.

To date the area has produced

  • 7mm+ oz Au
  • 220mm+ oz Ag
  • 3b+ lbs Cu

43-101 compliant resources and reserves of:

  • 65mm+ oz Au
  • 25b+ lbs. Cu

Figure 2 - Regional Map of  Deposits in the Homestake Ridge Area
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NI 43-101 Compliant Resource

In May 2011, the company issued a NI 43-101 compliant Technical Report on the Project which reported an indicated resource of 191,000 ounces of gold and 1,350,000 ounces of silver contained within 888,000 tonnes and inferred resources of 530,000 ounces of gold and 13,470,000 ounces of silver contained within 4,060,000 tonnes with an average cut-off grade of 3.0 g/t gold equivalent, (including the resource reported from 2010 in NR-10-05.)

Since the earlier June 2010 Technical Report was published, the inferred resource at Homestake Silver has been doubled, to the current resource, by an aggressive stepout drill program, (see NR-05-11).

Figure 4 - Long Section through the Main Homestake and the Homestake Silver Deposits
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The resource update, project audit and preliminary engineering work on project was conducted by Scott Wilson Roscoe Postle Associates Inc. (Scott Wilson RPA), who continue advise on pre-development and engineering aspects of the program. Melis Engineering Ltd. designed and oversaw metallurgical testing and reporting, All North Consultants is responsible for road design. Ridgeview Resources advises on permitting and environmental testing. Coast Mountain Geological Consultants is the primary geological contractor for the project and manages the in-field operations.

Figure 5 - 3d Wireframe Model of the Main Homestake and Homestake Silver Deposits
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The company now has clear guidance from Scott Wilson RPA’s work that the best economic path for Homestake will be via underground mining, which requires higher grades than an open pit, but which also requires far less surface disturbance and generally requires less initial capital for mine construction.

Table 1: At variable Aueq cutoffs, the current Mineral Resource estimate is as follows:

Notes:

  1. Homestake Main Indicated and Inferred Resources are restated from NR-07-10
  2. Homestake Main Resource at a 3.0g/t AuEq cutoff averages 0.21% Cu and contains an estimated 9.22 million lbs of Cu .
  3. CIM definitions were followed for Mineral Resources.
  4. Mineral Resources are estimated using an average long-term gold price of US$1,050 per ounce Au, US$18.00 per ounce Ag, and US$3.25 per pound Cu, with an exchange rate of C$1.00=US$0.90.
  5. Gold equivalence was calculated for the Main deposit using Au, Ag and Cu and and metallurgical recoveries of 85% Au, 75% Ag, 90% Cu.
  6. Gold equivalence for the Homestake Silver deposit was based on Au and Ag only, with no provision for metallurgical recoveries.
  7. A Ag:Au ratio of 62.5:1 was used to calculate the AuEq total (oz).

The current estimate was prepared by Roscoe Postle Associates Inc. (RPA). Mineral Resources on the Main Homestake deposit were estimated previously in 2010 using a block model constrained by 3D wireframes of the mineralized zones.  Mineral Resources on the Homestake Silver deposit were estimated in 2011 using a block model constrained by pierce points projected to 2D surfaces. The Main Homestake block model comprised an array of blocks measuring 5 m x 5 m x 5 m, with grades for Au, Ag, and Cu interpolated using ID3 weighting. The Homestake Silver block model comprised an array of blocks measuring 10 m x 10 m. At a 3.0g/t AuEq. cut-off, the models identified an indicated resource of 888,000 tonnes averaging 6.7g/t Au, 47.2g/t Ag and 0.15% Cu and a cumulative inferred resource of 4,060,000 tonnes averaging 4.3g/t Au, 158g/t Ag.

Exploration Highlights and Plans for 2011

Since acquisition of the property in 2003, the Company has aggressively explored the Homestake Ridge project and, by the end of 2010, had completed 216 diamond drill holes on the project for a total of 58,738 metres at a cost of +$25 million. Some of the geophysical targets have also been tested, which include the Fox Reef zone where narrow vein intercepts contain values up to 1g/t Au, 53g/t Ag, 1.3% Cu, 3% Pb and 8.34% Zn. All of the exploration holes drilled on the property in 2010 averaged around 0.1g/t Au. In addition, several exploration targets remain to be drill tested.

Figure 3 - Homestake Ridge Property Map showing Resources and Exploration Targets
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Property Highlights

  • 1,850m+ strike-length of precious metal mineralization from the Homestake Main to the Homestake Silver

Main Homestake Deposit:

  • 123 Drill Holes
  • 28,836 metres

Homestake Silver Deposit:

  • 55 Drill Holes
  • 21,713 metres

Permitting and planning for the upcoming field season are underway with the goals of identifying additional mineral resources on the Homestake Ridge Project and continuing in-house preliminary engineering and economic evaluations of the known deposits. The company anticipates a $2.5 million multi-phase exploration program that will focus on drill testing several newly established targets on the Homestake Ridge property, including the Southeast Extension of the Homestake Silver deposit, extensions of the newly discover 215 and Fox zones, and additional work on the previously identified Vanguard Copper, Vanguard Gold, North Dome and East Valley targets.

Bravo has also retained Fred Sveinson, P.Eng. in the role of Consulting Mining Engineer for the Homestake Ridge project.  Mr. Sveinson brings extensive experience in mine development, financing and operations to complement Bravo’s geological and corporate development teams.  He is a professional mining engineer with more than 40 years experience in all stages of mine development at operations who will work closely with Bravo’s current group of independent consultants to advance the ultimate development of the Homestake Ridge Project.


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Mineral Processing and Metallurgical Testing

Metallurgical test work has been undertaken by SGS Mineral Services in Lakefield, Ontario (SGS), under the close direction of Melis Engineering Ld. (Melis). Scott Wilson RPA has reviewed the work via the Melis reports as the test program progressed. Four different samples were created from quartered drill core to spatially represent the different zones of the deposit. An additional composite sample was created from three of the subsamples (Composite HR). Samples were subjected to a number of different processing options.

The initial work was focused on the Composite HR sample. A composite was made from five drillholes from the Homestake Silver Zone, but results were higher than what was expected to be mined and may not reflect true recoveries from this zone.

The initial assessment of four flowsheet options suggests that recovery of a combined gravity/flotation concentrate for sale to a smelter would be the simplest process and may prove the most economical, thus being the best option to pursue for future test work.

The sulphides within the Composite HR comprised 92% pyrite. Chalcopyrite accounts for 91% of the copper, with an additional 4.2% derived from tetrahedrite. Analysis indicates that liberation will require fine grinding with the D50 size being 50 microns for pyrite and 45 microns for chalcopyrite.

Gold deportment shows gold is present as free particles, attached or locked in, particles of pyrite and silicate minerals. Gold grains up to 100 microns in size were observed. Silver is present as native silver, electrum, kustelite, hessite, silver tetrahedrite, acanthite, pyrargyrite, and as an alloy with antimony. Silver tends to be locked up to a greater degree than gold.

Highlights of the work suggest:

  • That approximately 35% of the gold and 20% of the silver could be recovered in the gravity circuit and that
  • Flotation test conducted on gravity tailings indicates that there is little impact on performance from varying grind size. Two Locked Cycle Tests produced an average recovery of 85.5% for gold, 88.8% for silver, and 95.6% for copper.
  • Further work is recommended to assess metallurgical performance and improve concentrate grade.
  • Cyanidation tests indicate an average of 87% cyanide gold extraction from Composite HR gravity tails with a 48 hour leach time and suggest that additional recovery (compared to 85% from the flotation circuit) is likely too low to be economic.

Based on the results of metallurgical test work completed to date, the expected recoveries from a combined gravity/flotation processing plant would be:

  • 85% – 90% for gold 
  • 75% – 80% for silver 
  • 85% – 90% for copper

Environmental testing indicates the Composite HR tailing sample has a relatively high acid neutralizing potential and a very low potential for acid generation.

Historical Exploration and Current Exploration Models

Mineral occurrences on the property have been known since 1914. Modern work on the property, by Newmont Canada, Cambria Resources and Noranda, from 1979 to 1991, included mapping, surface sampling, trenching and limited diamond drilling. Much of this work targeted mineralization, similar to that at Red Mountain as well as epithermal mineralization in the Crown Grant area. Teck Cominco's work from 2000 to 2002 focused on the VMS potential of the property. Teck Cominco drill tested a small portion of the prospective stratigraphy and returned narrow but highly anomalous Au-Ag-Zn-As-Hg-Sb values along the "Eskay-type" horizon.

Mineralization at Homestake Ridge is spatially associated with a large volcanic center which occurs within the highly prolific Iskut-Stewart-Kitsault Belt. Over 80 separate mineral occurrences are located throughout the property and include extensive areas of precious and base metal mineralization related to the emplacement of a series of intrusive stocks and felsic dome complexes into the volcanic-sedimentary package.

Target deposit types include:
Silbak-Premier (4.3Mt @ 13.0 g/t Au, 273 g/t Ag): Hosted by lower to middle Jurassic andesitic to dacitic volcanics, ore zones formed a series of en-echelon high-grade lenses associated with strong silicification, sericite-kspar alteration and pyritization of the host rock.

Eskay Creek (2.6Mt @ 48.4 g/t Au, 2152 g/t Ag, 4.2% Zn, 2.5% Pb and 0.5% Cu): arguably the most significant economic discovery in BC of the last 15 years, this precious-metal rich VMS deposit is believed to be transitional between classic Kuroko VMS and High-Sulphidation Epithermal systems.

Red Mountain (12Mt @ 2.54 g/t Au): gold-copper mineralization is hosted by the phases of the Goldslide Intrusions and includes a high-grade core of 1.26Mt @ 8.0g/t Au.