The Buffonta property forms part of Osisko’s overall Garrison Project and is located in the Province of Ontario, approximately 100 kilometers east of Timmins and 40 kilometers north of Kirkland Lake. The property is situated on paved highway 101 that is shared with several producing mining operations with nearby labour, hydro power and supplies readily available.
The Buffonta property comprises 24 patented mining claims and 96 unpatented mining claims totaling 2396 hectares in Northeastern Ontario. The Buffonta property is owned 87.5% by Osisko Mining Inc. A process to get to 100% is currently in progress. It is located 4 km southeast of the Garrcon, Jonpol and 903 properties.
The Buffonta property is located in the western portion of the Abitibi Subprovince, an area covered largely in volcanic rocks and known to host numerous gold deposits, most of which occur near major fault zones.
The bedrock underlying the Buffonta mine group is comprised of weakly metamorphosed subaqueously deposited tholeiitic basalt and volumetrically minor intercalated interflow sediment of the Lower Blake River Group. Intrusive rocks include what is locally termed as the Garrison Stock, a 20 Km² monzonitic body located about 1 Km northeast of the Kerr pit. Felsic dykes intrude the supracrustal rocks in the Kerr pit area and in the footwall of the number 5 and number 6 zones. Some of these dykes are believed to represent apophyses of the Garrison Stock. Mafic dykes reported to be of lamprophyric and kimberlitic composition are also present. Local to the Garrison stock, higher grade metamorphism occurs as a metamorphic aureole around the Garrison stock with localized amphibolite grade facies.
The Archean supracrustal rocks underlying most of the claim group are approximately 3.3 Km south of the east striking structurally complex Destor-Porcupine Fault Zone. The Destor-Porcupine Fault Zone is spatially associated with many of the major gold deposits in the Abitibi Greenstone belt. The southern portion of the claim group is intersected by the Ghostmount Fault, host to the Holt-McDermott mine located approximately 12 Km to the northeast.
Gold tenors on the Buffonta mine group are known to occur in at least 3 distinct areas, termed as the Kerr Pit Zone, number 5 zone and number 6 zone. All 3 zones occur marginal to the Garrison Stock along locally northwest striking, south dipping Lower Blake River group meta-volcanic rocks subparallel to the inferred orientation of the Garrison Stock margin.
Shear hosted mineralization occurs in all 3 zones along the Buffonta-Turner Fault with the Kerr Pit Zone also hosting flat quartz veins. Mineralization at the Kerr Pit Zone occurs in amphibolite grade meta-volcanic rocks which form part of the contact metamorphic aureole around the Garrison Stock. Gold occurs in quartz veins and vein breccias around which are prominent grey to brown coloured pyritic alteration halos. The auriferous quartz veins are reported to fill planar fractures opportunistically and to range from 1-25 mm in width. Cryptic alteration halos surrounding the veins are millimetre to metre scale and carry pyrite constituting 10-20% of the visible alteration halo.
Visible native gold is known to occur within quartz breccia veins and within carbonate veins while microscopic native gold occurs associated with pyrite within and marginal to the quartz veins.
The core claim group was first staked in 1936 and incorporated as Amca Mines Ltd who submitted a 790 pound bulk sample to the Canada Department of Mines and Resources which graded 0.417oz/ton (14.3g/t) gold and 0.278oz/ton(9.2g/t) silver.
In 1937 under an option agreement with Hollinger Consolidated Gold Mines Ltd. an open pit measuring 24x18x9m deep was developed. A 75 ton per day mill was installed and mill feed from the open pit yielded 37 ounces of gold and 4 ounces of silver from an unknown volume of processed rock.
The property was subject to several campaigns of diamond drilling from 1938 to 1959 which delineated the number 5 and number 6 gold zones. During 1959 Thorncliffe mines was incorporated to explore the Buffonta mine group, and then sank a 3 compartment 33m deep shaft with one level at a depth of 30m. In 1961 Thorncliffe installed a 150 ton per day mill and produced over 200 ounces of gold from approximately 2000 tons (1814 tonnes) of material from the open pit zone.
Kerr-Addison mines acquired the property in 1980 and from 1981 to-1982 produced 9,000 ounces of gold from approximately 70,000 tons (63,500 tonnes). The ore was being shipped 145 Km to the Kerr-Addison mill in Virginiatown, Ontario.
In 1986 Silverside Resources optioned the property from Kerr-Addison mines and completed diamond drilling which extended the strike and depth of the number 5 and number 6 zones.
In 1987 the remaining interest of the property was optioned from Kerr-Addison by Proteus Resources and Lac Minerals who completed additional diamond drilling and geophysics. In 1989 the companies reported to have drill indicated resources in the three zones which totaled 600,000 tons at a grade of 0.175oz/ton (6.0g/t). (2)
In 1990-1991 Gwen Resources mined 26,643 tonnes from the number 6 zone which yielded 2,902 oz. of gold. The ore was shipped to the Kerr-Addison mill in Virginiatown, Ontario. (1)
HISTORICAL RESOURCE CALCULATION (NON 43-101 COMPLIANT)
A resource calculation completed by M.V.W. White & Associates Ltd in 1997 for Gwen Resources totaled the resources on the Buffonta Property as such:
|6 Zone||5.77g/t||73,207 tonnes||13,583oz|
|5 Zone||4.82g/t||140,988 tonnes||21,860oz|
|Kerr Pit||4.84g/t||193,520 tonnes||30,134oz|
*All assays are historic in nature and as such do not comply with NI 43-101 requirements and therefore, should not be relied upon. All results are reported from 3rd party reports referenced below. No qualified person has verified the numbers and therefore they should not be relied upon.
- Barron, K.M. 1992. Geological Investigation of the New Buffonta Kimberlite. Gwen Resources.
- White, M.V. 1997. Evaluation Report on the New Buffonta Property. Gwen Resources.
Osisko is reviewing existing data to access the potential at the Buffonta property. Osisko will continue the baseline environmental studies and will maintain the good relationship that the project is benefitting from with local communities and First Nations.