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BRONSON SLOPE

The Bronson Slope gold project is Skyline Gold Corporation's primary and most well known asset. The property is 100% owned by Skyline. The 158.1 hectare property is located in the metallogenetically important Stewart-Iskut River area in the heart of the world renowned Golden Triangle of northwestern British Columbia. The Property is 110 km northwest of Stewart, B.C., 280 km northwest of Terrace, B.C., 80 km east of Wrangell, Alaska and 70 km west of Bob Quinn airstrip on the Stewart-Cassiar Highway. A mine access road leads from Bob Quinn 40 km down the south side of Iskut River to within 30 km of Bronson Slope where it turns south to the Eskay Creek gold-silver mine of Barrick Gold.


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Two airstrips suitable for Hercules aircraft or equivalent service the Property. One occurs at 100m elevation at Bronson Airstrip, which is the old campsite of the closed Snip Gold Mine just north of the property. The second occurs in the alpine at 1100m elevation at the closed Johnny Mountain Gold Mine in the centre of the adjoining Iskut property. In recent years helicopters working for the mineral exploration industry out of Bob Quinn airstrip have been available for work in the area. This availability of helicopters is expected to continue in the 2006 field season.

The Bronson Slope copper, gold, silver, molybdenum mineralization is considered to be a porphyry copper, gold deposit type. It was first investigated as a porphyry deposit in 1962 by Cominco, but largely ignored until 1993 when Skyline, which owned the property as part of its Johnny Mountain land package took it on as an exploration play under the leadership of Cliff Grandison, a former executive of Placer-Dome. Skyline initiated a pre-feasibility study during 1996 and 1997 based on 77 holes representing 14,800 metres of drilling.



GEOLOGY


The Bronson Slope Property is underlain by the Early Jurassic Red Bluff porphyry gold-coppersilver-molybdenum hydrothermal system that is dominated by an intense quartz-magnetitehematite stock work that trends northwest along the south side of Bronson Creek valley. The image below provides an overview of the regional geology.


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The Red Bluff porphyry is intrusive into Upper Triassic age feldspathic greywacke. The stockwork overprints and is intimately associated with the Red Bluff porphyry intrusion. The stockwork is composed of an intense network of veins. Drill intersections of 20 to +100 metres long are composed entirely of intersecting to sheeted sets of quartz, magnetite, hematite veins. Individual veins range from 0.5 to 10 cm in thickness. The quartz, magnetite, hematite stockwork is overprinted by quartz + pyrite + chalcopyrite +/- carbonate veins and by carbonate and pyrite veins. The total sulphide content in the quartz, pyrite assemblage is around 5%. The quartz, pyrite assemblage comprises less than 10% of the older quartz, magnetite, hematite veins. The quartz-pyrite veins/alteration are locally brecciated.

Gold and copper grades reflect the distribution of the different veins and alteration types. Areas of quartz, magnetite, hematite veining with sparse or no pyrite, chalcopyrite or quartz, pyrite overprinting have low gold and copper grades. Higher copper and gold grades occur in quartz, pyrite, chalcopyrite veins and alteration and in areas of abundant pyrite, chalcopyrite veining both inside the quartz, Fe-oxide stockwork and in adjacent greywacke. The greywacke are massive to crudely bedded. Individual graded beds may have sharp, scoured basal contacts and may contain siltstone or mudstone rip up clasts.

A folded sequence of turbiditic feldspathic greywackes with subordinate inter-bedded siltstones, mudstones, volcanic conglomerate and rare carbonate lenses is intruded by the Red Bluff porphyry. The sequence is weakly to moderately metamorphosed (lower greenschist facies). Alteration ranges from weak to strong in the vicinity of mineral prospects. Pebble to cobble sized clasts of fine grained and porphyritic mafic to felsic volcanic rocks are present in coarser beds, and coupled with the common presence of angular to sub rounded plagioclase grains in greywacke units, imply a proximal volcanic source. These rocks are probably lateral equivalents of Stuhini Group strata exposed on Snippaker Ridge 4 km southeast of Bronson Slope, which contain Upper Triassic fossils.

Early Jurassic felsic to intermediate volcanoclastic, pyroclastic and flow rocks that probably belong to the Lower Hazelton Group are exposed on Johnny Mountain. They are flat-lying to moderately tilted and unconformably overlie the greywacke sequence noted above. The sequences are separated by a flat lying to gently dipping regional unconformity exposed approximately one kilometre to the northeast of the Johnny Mountain Gold mine.

The Bronson stock, also known as the Red Bluff Porphyry Intrusion, is a heterogeneous, medium-grained equigrangular plagioclase + clinopyroxene +/- amphibole phyric diorite. The stock lies north of the former producing Snip gold mine. A poorly constrained Late Triassic U-Pb zircon age date of between 197Ma and 225 Ma was obtained from a K feldspar + plagioclase phyric monzodiorite phase of this unit (Macdonald et al, 1992). Several small stocks, sills and dikes of unknown age and intermediate to mafic composition intrude the Bronson stock. Lamprophyre dykes of probable Jurassic age have been mapped at numerous locations on the property and in addition lower Jurassic feldspar porphyry dykes and Tertiary intrusive stocks have been noted. Basalt dykes, possibly correlative with Recent volcanism, have also been observed.

The lower sequence is intruded by the Red Bluff porphyry stock (Bronson Slope deposit), a hydrothermally altered, potassium feldspar megacrystic, plagioclase porphyritic intrusion of probable granodioritic composition. The stock is approximately 2.0 kilometres long, up to 0.3 kilometres wide and trends southeast along the southwest side of the Bronson Creek valley. Contacts of the stock with country rocks are not well defined, but where observed in drill core or underground workings are either faulted or intrusive. The southwest and northeast contacts appear to be southwesterly dipping. Screens of altered greywacke up to 40 m wide are common throughout the intrusion. The age of the Red Bluff intrusive is Lower Jurassic.

The Red Bluff porphyry is a hydrothermally altered K-feldspar megacrystic, plagioclase porphyritic intrusion of probable quartz diorite to quartz monzonite composition. Subhedral tabular pink K-feldspar phenocrysts generally range in length from 2 mm to 20 mm. They usually comprise from less than 1% to 5% of the modal mineralogy. The matrix to the K-feldspar megacrysts consists of medium-grained porphyry containing phenocrysts of albitic plagioclase, altered amphibole and quartz. The plagioclase is usually completely altered to aggregates of sericite+/- quartz +/- K-feldspar. Mafic phenocrysts, probably original hornblende from grain shapes, are commonly altered to magnetite, hematite, pyrite, biotite, and chlorite. Equant, clear to smoky sub rounded quartz phenocrysts, 0.2 mm to 1.5 mm in diameter, comprise less that 1% to 4%. In areas of moderate to intense alteration original quartz is difficult to identify. Accessory minerals include apatite, zircon and titanite. The fine-grained matrix to the phenocrysts forms between 35% and 70% of the rock volume.

Click here for a virtual tour of the Bronson Slope deposit
HISTORICAL EXPLORATION AND DRILLING

Bronson Slope was originally staked in 1911 and is characterized by a 245 metre Red Bluff on the south bank of Bronson Creek. Between 1916 and 1920, two adits were driven, as well as several open cuts, which exposed good prospects in gold and copper. In 1919, a vein was reported along this side-hill that assayed values of copper, silver and gold across about 9 metres.

Skyline personnel have worked on the Property since 1988 and it was during a 1992 review of all exploration and drilling data by Burgoyne that the alteration and then defined mineralization indicated the potential for a large low-grade porphyry copper-gold deposit. In 1993 Skyline performed Induced Polarization and Chargeability surveys and a limited drilling program of 872 metres over 7 drill holes on two separate cross-sections of the deposit. This program was successful and is recognized in partially defining the Bronson Slope porphyry copper, gold deposit. A total of 14,714 metres of drilling over 77 diamond drill core holes were drilled in 1965, 1984, 1988 and from 1993 through 1997. This drilling has defined the historical resource. All reference to the deposit are historical in context.


In 1995, with Explore B.C. Program support, International Skyline Gold Corporation carried out a 7 hole diamond drilling program totalling 2428.6 metres. The project was advanced to the mine development stage and an Approval Certificate Application made as the first step in the Environmental Assessment Review.

About 400 metres uphill of this target area, Skyline has traced a near surface structure of disseminated and stockwork gold mineralization known as the Highwall zone. The zone can be followed along strike for about 800 metres on Skyline's property. The zone likely represents the easterly continuation of the deeper, high-grade structure mined at the Snip deposit.

Also during 1996 and 1997 Skyline completed a substantial amount of engineering scoping, environmental, cash flow, metallurgical, capital and operating costs, geotechnical, infrastructure and access, and other pre-feasibility studies on the Bronson Slope deposit.

In late July 1997 the Company was able to announce the acquisition of two key mineral titles from Prime Resources Group Inc., which helped to enhance the Bronson Slope project. The two properties, the Kathleen fraction and the High Wall, are adjacent to Skyline's Bronson Slope. The Kathleen fraction allowed Skyline to consolidate its four principal Bronson Slope claims into one continuous block.

Upon acquisition of the High Wall area (of the Bronson Slope deposit) from Prime Resources Group, Skyline also obtained access to previously drilled core completed in this area. Skyline's 1997 program included the surveying of 7 historic core holes, re-logging of the drill holes, core splitting, and geochemical analyses of previously unsampled porphyry mineralization. A six hole drill program conducted on the High Wall zone in 1997 defined a zone of gold mineralization with a strike length of 800 metres parallel to both the Bronson Slope porphyry deposit and to the Snip shear zone vein deposit.



HISTORICAL MINERAL RESOURCE

Several resource estimates were undertaken by Skyline in the period of 1994 through 1997. Some of the initial estimates were done mainly to identify zones of mineralization for future drilling and define tonnage ranges for future engineering studies. C.M. Turek, P.Eng., undertook the in-house Skyline resource estimates, at the time using the PC-EXPLORE software of Gemcom Services in Vancouver. The second group of resource estimates were completed during the period April 1996 to July 1997 using outside consultants G.H. Giroux, P. Eng. and G.F. Raymond, P.Eng. At the time of the consultant's estimates and later, Skyline also engaged Mr. W. Martin, P.Eng., a Skyline employee, to undertake combined resource/mine plan estimates for modelling and economic analyses using SURPAC software and Whittle optimization pit plan.

The historical resource estimate is discussed below with the Giroux (1996b) historical mineral resource estimate being considered the base case.A block model and ordinary kriging were used to determine the resource. This estimate should be considered as the base case for the Bronson Slope property. The base case estimate, at US $1.00 equivalent to C$1.33, a US $6 NSR (Net Smelter Return) cut off, after using US $ 385 / ounce for gold, US $5.25 / ounce for silver, and US $1.10 / pound for copper and metal recoveries, smelter payments, refining charges, treatment charges and transportation is given in the table below


BRONSON SLOPE HISTORICAL
RESOURCE - BASE CASE (Giroux, 1996b)
Cut Off US $ 6 NSR
Category Tonnes Au /gt Ag g/t Cu%
Measured 2,280,000 0.574 2.59 0.210
Indicated 65,000,000 0.527 2.46 0.196
Total Measured+Indicated 67,280,000 0.528 2.46 0.196
Inferred 24,300,000 0.454 2.23 0.199


This estimate does not include all drilling (drilling subsequent to the estimate) but it appears accurate for the database used. The Giroux estimate is sufficiently detailed in presentation and is, in the opinion of the Skyline's geologist, is considered to be a fair and reliable estimate for the database used.

The Giroux (1996b) and Raymond (1997) resource estimates are considered reliable, with respect to the then metal prices used in 1996 and 1997 and are thus considered Historical Resources.

This Giroux base case resource estimate and the Raymond estimate do not meet NI 43-101 and CIMM standards for resource definition largely because of the age (10 years) and the fact that QA/QC controls, as we know today, were not present; also the NSR cut off was based on defined 1996 metal prices (noted above), treatment charges, smelter payments, refining charges and transportation charges and estimated operating costs that are clearly not valid today.

In addition to the above resource, Skyline, in late 1997, completed preliminary estimations as to the size and grade of the High Wall Gold Zone, which is located on the south side of the deposit, within the High Wall area of a potential open pit. There is no formal independent resource report and the resource estimations done by Skyline are not 43-101 or CIMM compliant and are not relevant on this zone. However, drilling indicates an exploration potential in the range of 12 to 15 million tonnes grading 0.5 to 0.6 g/t gold.

BRONSON SLOPE
HISTORICAL RESOURCE ESTIMATES
Study* Date Method Category** Tonnes Au g/t Ag g/t Cu % Mo NSR
US $ 6 NSR Cut Off(millions)ppm
GirouxApril 30 96Kriging 100mInd54.70.5572.380.1868.89
40 ddhInf20.70.4731.840.1697.69
Kriging 250 mInd53.00.5572.370.186
Inf84.50.4551.800.166
GirouxOct 8 96Kriging 100 mMeas + Ind67.30.5282.370.1968.72
47 ddhBase CaseInf24.30.4542.230.1997.95
Kriging 250 mMeas + Ind67.30.5292.370.1968.72
Inf103.00.4592.340.1827.77
GirouxDec 16 96Kriging100 mMeas + Ind74.50.5592.650.1989.10
56 ddhInf
Kriging250 mMeas + Ind78.40.6382.740.1949.87
Inf103.60.7182.870.17510.45
GirouxMay 1 97Kriging100mMeas + Ind85.90.5903.050.1638.91
63 ddhInf41.10.6293.620.1168.66
Kriging 250 mMeas + Ind90.60.6463.070.1599.47
Inf179.70.6703.350.1239.20
RaymondJuly 15 97KrigingMeas + Ind63.40.552.590.197658.97
62 ddhPolygonMeas + Ind55.40.6523.270.2257510.53
* ddh = diamond drill hole
* * Meas = Measured
Ind = Indicated

HISTORICAL DRILL HOLES

SUMMARY OF DIAMOND DRILLING
BRONSON SLOPE DEPOSIT
Period Company Drilling Contractor Core Size* Hole Numbers Holes Meters
1965 Cominco Cominco Packsack 1073 to 1080 7 337
1986 Cominco BQ S 6 1 108
1994 Prime Resources Olympic Drilling BQ S101, S125-127, S129, S130 6 2224
1988 Skyline Falcon Drilling BQ tw 944 to 949, 954 to 964 17 1,938
1993 Skyline Boisvenu Drilling BQ tw 1198 to 1204 7 872
1994 Skyline Olympic Drilling BQ tw 1208 to 1216 9 1,550
1995 Skyline Olympic Drilling BQ tw 1217 to 1223 7 2,429
1996 Skyline Britton Brothers BQ tw 1224 to 1239 16 3,529
1997 Skyline Britton Brothers NQ** 1240 to 1246 7 1,835
* tw = thin wall ** One HQ hole Totals 77 14,714


FUTURE EXPLORATION & DRILLING

Skyline Gold Corporation plans a 2 stage drilling program for the summer of 2006 and 2007 which will be initiated at the Bronson Slope deposit. The Stage one, will including drilling, will cost an estimated $1.75 million. This will be followed by a Stage two program, assuming positive Stage one results, where a majority of the work will be drilling, with costs estimated at $3.7 million.

A field exploration camp will be established at the Bronson airstrip.

It is in the company's opinion that a high potential exists to upgrade the historical resource to a current measured and indicated resource and discover additional mineralization at the Bronson Slope site.

The Stage one program will involve pre-season planning and evaluation (currently underway), survey control and tie-in to pre existing grids and geological databases and diamond core drilling of about 4,215 metres.

The Stage two program will continue, assuming positive Stage one results, but will be primarily directed at diamond drilling approximately 10,655 metres using two drill rigs.

The 2006/07 summer drill plans will focus on several key areas, firstly a comprehensive Quality Control / Quality Assessment program will be established for core drilling. Preliminary metallurgical gold recovery studies will be completed on existing High Wall drill core as no studies have been done on this mineralization.

The QA/QC program to be introduced will run for the life of the drill programs and give high confidence to the drill analytical data. In addition the company will reanalyze existing historical drill core, complete more in-fill drilling and some twinned holes in the drilling program of Phase one.

Drilling will be done on 50 metre centres for definition of measured resource and 100 metre centres for definition of indicated resource with continued infill drilling on the Red Bluff portion of the deposit. Drilling will continue to define mineralization extent and to increase mineral resource confidence.

Skyline's objective will be to continue drilling the High Wall portion of the deposit to define the gold-bearing portion of the deposit to at least the indicated category as a current resource, as well as, continue exploration drilling on the Bronson East and Bronson West portions of the deposit to define additional resource.

The Company will seek to contract drill rigs that are preferably wire line HQ core diameter, or at minimum, NQ core diameter. The larger core diameter will allow for a more representative sample to be obtained, particularly for gold analyses and for possible later metallurgical and/or geotechnical studies.

Once the Stage one drilling is completed a revised insitu current resource estimate will be completed using the kriging methods adapted and modified by Giroux and Raymond using all drill hole data, including the High Wall zone, and using measured specific gravities from all rock types.

Metallic gold analyses will be completed to see if there is a significant coarse grained component of the total gold content, while gold assay will be completed on 50-gram pulp samples by fire assay with an atomic absorption finish. Silver, copper, and molybdenum analyses can be done on one-gram pulp samples by the four acid digestion method of hydrochloric-nitric-perchloric-hydrofluoric acids.

As a guide to future drilling and to define additional mineralization, the table below summarizes the location, priority and amount of drilling required.


BRONSON SLOPE DEPOSIT DRILLING REQUIREMENTS
Infill (50 m spacing) and Detailed Exploration (100 m spacing) Drilling Requirements
DEPOSIT MINERALIZATION PRIORITY TOTALS
AREA ZONE High Medium Low
    # Holes Length m # Holes Length m # Holes Length m # Holes Length m
Red Bluff (50m) Au, Cu Core 14 3665 6 1560 3 440 23 5665
High Wall (100m) Au, Pyrite Shell 6 1040 7 1225 13 2265
Bronson East (100m) Au, Cu, Mo Extension 2 550 5 1440 15 3800 22 5790
Bronson West (Explore) Au, Cu Exploration 2 370 4 780 6 1150
TOTALS: 16 4215 19 4410 29 6245 64 14870


*The Qualified Person(s) responsible for the information regarding the Bronson Slope property given on this website is Al Burgoyne Ph. Eng. and David Yeager P. Geo.  
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