The main silver rich zones on the property are the Oban, Talisker and Glenfiddich Zones. The three zones combined were the subject of an inferred NI-43-101 resource estimate conducted by SRK Consulting (Canada) Inc., (October 28, 2014). They host potential for economic deposits of intermediate to high sulphidation Ag-Au-Zn-Pb-Cu as breccia-veins (Talisker, Glenfiddich) and diatreme breccia (Oban). These zones remain open for expansion along strike and at depth.
- Diatreme & breccia veins (high-intermediate sulphidation).
2014 inferred resource of 21.5 Moz AgEq, 7.4 Mt at 89.75 g/t AgEq (SRK October 28, 2013).
- Three zones combined make up the resource: Oban, Talisker and Glenfiddich.
- Oban is a diatreme breccia with a silver rich core, Ag-Au-Zn-Pb-Cu, remains open.
- Talisker and Glenfiddich Zones are breccia-veins, Ag-Cu-Au, remain open.
- Modeled after Far-South-East & Lepanto (Philippines), porphyry at depth.
- Many surface rock samples returning greater than 20 g/t Au require follow up.
- Unconformity follow up: drilled 12 g/t Au/1 m within 20 m of 1 g/t Au.
- Large gossan northwest from the camp has yet to be sampled.
- Drilling for Talisker Zone extension east encountered Oban style diatreme suggesting a second diatreme exists.
- A 30 km gold-silver trend (King Salmon Lake to Trapper lake).
First diamond drilling at the Oban, Talisker and Glenfiddich Zones was done by American Reserve Mining Corp. and Inland Recovery Group in 1986 when five holes were drilled at the Glenfiddich Zone. Since then, on the three zones combined, approximately 15,200 metres of drilling was done by First Au, Rimfire, Cangold and Brixton Metals. Other exploration work included soils and rocks geochem, IP, HLEM, Airborne EM and Magnetics, multispectral Aster data processing and structural geology study.
In 2014 Brixton Metals commissioned SRK Consulting to provide NI-43-101 maiden resource at the Thorn Project.
Table 1.1: Inferred Mineral Resource Statement, Thorn Project, British Columbia, SRK Consulting (Canada) Inc., October 28, 2014.
The in-pit portion is reported at a dollar equivalent cut-off value of US $15 per tonne within a Whittle shell and $50 per tonne for an underground portion of the Oban deposit. The Whittle shells were designed based on a slope angle of 55 degrees and 90% recovery for all metals. The block models are 10 x 10 x 10 m, 5 x 10 x 5 m, and 5 x 10 x 5 m for Oban, Glenfiddich, and Talisker, respectively. The Whittle shell for Oban does not include copper. The Whittle shells for Glenfiddich and Talisker do not include lead or zinc.
Dollar and Silver Equivalents are based on US $20 Silver, $1200 Gold, $3 Copper, $1 lead, and $1 zinc, with metal recoveries of 90%. Copper is not included in the Oban estimates. Lead and zinc are not included in the Glenfiddich and Talisker estimates.
The three silver zones, Oban, Talisker and Glenfiddich are hosted by the Thorn Stock, a diorite porphyry which is nonconformably overlain by the Windy Table volcanic rocks, both Cretaceous in age. The Oban Zone is a diatreme breccia with sub-zones of hydrothermal breccia. Rounded to angular fragments are dominantly Thorn Stock. Alteration within the Oban Zone is dominated by carbonate, K-spar and is generally silica poor, +- flourite. Most of the mineralization is matrix supported with the occasional-rare mineralized fragment. The Oban Zone mineralization is polymetallic as silver, gold, zinc, lead and copper. Mineralization is associated with sulphide/sulphosalts as pyrite, tetrahedrite, sphalerite, chalcopyrite and galena.
Silver-gold-copper mineralization at the Talisker and Glenfiddich Zones trend to the northeast they are structurally controlled high-sulphidation brecciated-quartz-sulphide zones hosted in the Thorn stock. The major minerals occur as pyrite, tetrahedrite and enargite.
Drilling at the Oban zone consists of approximately 11,250 m, 1,450 m at the Glenfiddich Zone and 2,760 m at Talisker. Best hole at the Oban Zone was hole 60 which intersected 95.08 m of 628 g/t Ag, 1.71 g/t Au, 3.31% Pb, 2.39% Zn and 0.12% Cu. Other significant drill intercepts are summarized in the table below:
Oban Zone Select Drill Results
Talisker Zone Select Drill Results
Glenfiddich Zone Select Drill Results
Drill hole Location Map for Silver zones
Other mineralized veins:
- Confirmed the presence of a broad fault/vein zone at the Lagavulin Vein, including 75 m grading 7.14 g/t Au, 245 g/t Ag and 0.35% Cu in THN11-54
- Intersected narrow Cu-rich veins at depth corresponding to the MP Vein, including 74 m grading 4.14% Cu, 384 g/t Ag and 1.22 g/t Au in THN11-45
Silver equivalent (AgEq) values were calculated using $1,088 per ounce of gold, $19.62 per ounce of silver, $3.20 per pound for copper $0.80 per pound of lead, $0.80 per pound of zinc, all with 100% metal recoveries assumed.
AgEq = Ag g/t + (Au g/t x 34.98/0.63) + (Pb% x 17.64/0.63) + (Zn% x 17.64/0.63) + (Cu% x 70.55/0.63)
The three zones were the subject of multiple soils and rocks geochem programs. The analytical results show a strong silver and gold geochem anomaly with values as high as 611 g/t Ag and 20 g/t Au in soil samples and 5,434 g/t Ag and 25.9 g/t Au in rock samples.
During 2000 – 2010, the three zones were evaluated by Rimfire, Cangold and Brixton Metals with a number of ground and airborne geophysical surveys:
- Rimfire (2000) – 384 line-km airborne EM, magnetics
- Cangold & Rimfire (2004) – 31.1 line-km IP/Res, 7.5 line-km HLEM
- Cangold & Rimfire (2005) – 17.4 line-km IP/Res
- Brixton (2010) – 467 line-km airborne EM, magnetics
The processing of the Induced Polarization data highlighted very strong chargeability anomalies at the Oban, Talisker and Glenfiddich Zones. See maps and profiles below: