Work History
A series of north-south trending hand trenches likely dug in the 1920's uncovered a quartz vein. No claims were apparently staked at the time and no subsequent work is documented.
In August 1989, E. Curley rediscovered the vein, staked Grizzly cl 1-24 (YB26488) and carried out bulldozer and hand trenching and geochemical rock sampling later in the year. Rock sampling was also carried out by Noranda Exploration Company Ltd. and Total Energold Corporation in the fall of 1989. Additional bulldozer trenching was carried out by Curley in 1990.
Re-staked by Curley as Grizzly cl 1-6 (YB46485) in October 1993. In August 1994 Teck Exploration conducted a short property evaluation. Teck mapped and sampled several of the trenches located on the property. Although Teck recorded lower assays than previously published, the company recommended that further work be carried out to test the strike and dip potential of the main vein. Curley carried out further prospecting and sampling in October 1994.
Re-staked as JRW cl 1-4 (YC19850) in October 2002 by J. Dickson who carried out a limited rock and reconnaissance soil sampling in 2003.
Re-staked in 2010 by Strategic Metals as the Dade cl 1-16 who performed one day of soil sampling. The Dade cl 17-96 were added to the claim package by Strategic later that year. In 2011, Strategic carried out soil sampling, prospecting, mapping, trenching and helicopter-borne magnetic and radiometric geophysical surveys over the property, including the Grizzly occurrence. In 2012, Strategic carried out diamond drilling of 23 holes totaling 1426.47 m and RC drilling of 24 holes totaling 1426.47 m at the Grizzly occurrence.
Rockhaven acquired the claims from Strategic Metals and carried out soil sampling near Grizzly in 2016.
Regional & Property Geology
The occurrence area is underlain by Proterozoic to Paleozoic amphibolite and serpentinized ultramafics of the Yukon-Tanana Terrane overlain by the Late Devonian to Mississippian Pelly Gneiss Suite biotite to hornblende granodiorite gneiss. A Cretaceous syenite plug intrudes these rocks in the northwest. A stock of middle Cretaceous Whitehorse Suite granodiorite underlies the western portion of the property and cuts amphibolite units and syenite. Middle Cretaceous Mount Nansen andesite to dacite flows cap the Whitehorse Suite intrusion and metamorphic package. A series of Late Cretaceous to Tertiary quartz-feldspar porphyry dykes cut the Pelly Gneiss Suite immediately northeast of the property, and about one kilometre southwest of the property a stock of Late Cretaceous biotite-hornblende quartz monzonite intrudes the Whitehorse Suite Stock and Mount Nansen Group volcanics (AR 096434).
In the Grizzly area, mapping noted outcrops of Pelly Gneiss Suite on the eastern and northeastern property edges. The northern part of the property as three exposures of Late Cretaceous Prospector Mountain Suite coarse-grained hornblende-quartz diorite (AR 096434).
Mineralization & Results
Surface mineralization on the Dade property, including the Grizzly occurrence, is hosted in stockwork quartz veins with pervasive silicification and moderate to strong clay alteration. These veins crosscut hornblende-quartz granodiorite to diorite gneiss and are comprised of boxwork limonite and 1 to 3% disseminated arsenopyrite and pyrite. Sub-economic grades were also noted in quartz-ankerite veins with no visible suphides.
In an old hand trench on the Grizzly claims, Curley found vein float containing 42.5 g/t Au, 59.94 g/t Ag, 185 ppm Cu, 979 ppm Pb, >30 000 ppm As, 91 ppm Sb, 34 ppm W and 410 ppb Hg. Further trenching exposed a quartz-arsenopyrite vein up to 6 m wide with a hanging wall of propylitic altered andesite and footwall of sericite altered andesite porphyry or dykes(?) of the Late Cretaceous to Paleocene Mount Nansen Volcanic Suite. The vein strikes ENE and dips 60° west, was traced discontinuously over strike length of 140 m and occupies a fault zone cutting early Jurassic hornblende syenite of the Mount Freegold Meta-Plutonic Suite. Two chip samples from the vein assayed 7.2 g/t Au over 3.5 m and 15.4 g/t Au over 1.5m. Porphyry copper and molybdenum mineralization also occurs on the property. The veins appear to be controlled by dilational fractures peripheral to the porphyry mineralization.
Although Teck attempted to replicate Curley's earlier assays, its best assay was 3.5 g/t Au. Teck felt that the lower values were related to the erratic nature of gold and variations in the amount of sulphide in the vein. Teck recommended further trenching, particularly towards Grizzly Creek, since gold values increased in that direction.
Sampling in 2003 returned lower values than previously reported, possibly due to the limited amount of sampling (3 rock samples) carried out. A rock chip sample collected across the vein at this time returned 1 237.8 ppb Au over 2.2 m. Soil samples anomalous in Au, As and Bi indicate a possible strike extension of the vein 200 m to the northeast. A soil sample anomalous in As collected 420 m southwest of the trenched area may also indicate an extension of the vein or possibly a new mineralized source in that area.
Soil sampling in 2010 and 2011 by Strategic returned rare strongly anomalous values of up to 166 ppb Au. Samples collected near historical trenches returned up to 7.26 g/t Au, 1% As, 554 ppm Sb, 93.9 ppm Ag and 1060 ppm Cu. Trenching in 2011 uncovered a second sinusoidal zone of quartz veining and returned grades of 1.71 g/t Au over 32 m, including 10.14 g/t Au over 4.0 m and 0.86 g/t Au over 3.0 m.
Diamond and RC drilling performed by Strategic in 2012 encountered zones of finely banded chalcedony and jigsaw breccias associated with porphyry dykes with trace finely disseminated pyrite and arsenopyrite. The best results from diamond drilling returned 2.05 g/t Au over 3.05 m in DDH-12-02 and 2.44 g/t Au over 1.2 m in DDH-12-14. The best results from RC drilling were 5.32 g/t Au over 1.53 m in RCH-12-21 and 2.28 g/t Au over 1.52 m in RCH-12-22.
