The Hanson Lake East (Cyr) occurrence is located at an elevation of approximately 1060 metres on a south-southeast–facing slope, approximately 2 kilometres northeast of the northeast end of Hanson Lake.
The area is underlain by a metamorphic complex comprised of metamorphosed equivalents of the Carboniferous-Jurassic Cache Creek Group and a gneissic complex of granodiorites and quartz diorites. These were intruded by Tertiary intrusives. Basic to acid dikes and stocks are common. Lithologies include quartz monzonite, quartz porphyry, quartz feldspar porphyry, acid breccia, quartz diorite and amphibolite. Argillic and chloritic alteration is evident in the quartz monzonite. The other lithologies show strong argillic, silicic, and sulfidic alteration.
Mineralization consists of 1) fracture filling copper and molybdenum in quartz monzonite 2) silicified zones containing gold, silver, zinc and lead in quartz porphyry/quartz feldspar porphyry 3) silicified zones containing zinc, lead, gold and silver in acid breccias trending north 4) shear zone containing copper and gold in quartz diorite/amphibolite. Sulphides occur mainly as pyrite, chalcopyrite, sphalerite, molybdenite and galena.
The Cyr zone is underlain by a quartz porphyry unit. This porphyry is commonly clay altered, oxidized, and is often leached and vuggy. The porphyry appears rhyolitic or dacitic in composition and may be a high level intrusive. The rhyolite may belong to the Eocene Ootsa Lake Group. Mineralization in the Cyr zone occurs as disseminated pyrite which is ubiquitous throughout the quartz feldspar porphyry. Quartz veins and quartz segregations are found locally but do not appear associated with sulphide mineralization.
Work History
During the 1960s and 1970s, a regional stream sediment reconnaissance program was conducted in Hanson lake area by Endako Mines staff. Anomalous metals were found in streams draining into Hanson Lake from the north and south. A 2 kilometre by 9 kilometre, zinc-lead anomaly with locally high silver-copper and outlying areas of high copper-molybdenum was defined by soil sampling. Induced polarization and magnetic anomalies were tested by trenching and diamond drilling with subeconomic mineralization being locally intersected. In the mid 1970s, the property was acquired by Placer Dome and widely spaced diamond drilling was performed in 1977 and 1979 on monzonite targets south of Hanson Lake (093K 081).
In the late 1980s and early 1990s, Cazador Explorations conducted geological mapping, rock sampling, geochemical and geophysical surveys, and an extensive diamond-drilling program on the Hanson Lake property.
In 1988, re-sampling of drill cuttings from the 1972 and 1973 Placer Dome drilling yielded up to 0.70 per cent copper and 38 grams per tonne silver over 3 metres and 3.80 per cent zinc, 1.00 per cent lead with 20 grams per tonne silver over 3 metres in hole H3; 0.11 per cent copper with 0.18 gram per tonne gold over 3 metres in hole H4; 0.3 per cent zinc over 83.82 metres in hole P25 and 0.4 per cent zinc with 34.2 grams per tonne silver over 30.48 metres in hole P27 (Assessment Report 18398 and 34832).
In 1989, reverse circulation drilling on the Cyr zone yielded intercepts of 0.38 per cent zinc over 100 metres, including 0.20 and 0.18 per cent lead, 0.49 and 0.86 per cent zinc, 3.6 and 4.0 grams per tonne silver with 0.16 and 0.22 gram per tonne gold over 22 and 14 metres, respectively, in hole RC8911; 0.27 per cent zinc over 100 metres, including 0.48 per cent lead, 1.07 per cent zinc, 14.6 grams per tonne silver and 0.34 gram per tonne gold over 10 metres, in hole RC8912; 0.62 per copper, 80.0 grams per tonne silver and 1.84 grams per tonne gold over 2 metres in hole RC8917 and 41.9 grams per tonne silver with 0.72 gram per tonne gold over 10 metres in hole RC8921 (Assessment Report 19155).
Later that year, trench RC-21 yielded 2.72 grams per tonne gold and 138.4 grams per tonne silver over 6 metres (Assessment Report 19649).
In 1990, drilling yielded intercepts including 23.9 grams per tonne silver over 30 metres in hole DH90-4 and 0.90 per cent zinc with 8.3 grams per tonne silver over 33 metres in hole DH90-5 (Assessment Report 21187).
In 1995, Columbia Yukon Resources, under an option with Metamin Enterprises Inc., completed four drill holes, totalling 961 metres, on the Bysouth zone to the west.
In 2004, Abel Exploration Ltd. completed a small program of lithogeochemical sampling of historical trenches on the Kimura and Cyr zones. A sample (R172101) from trench RC-21 yielded 0.63 gram per tonne gold and 29.3 grams per tonne silver (Assessment Report 27865).
In 2006, G.W. Kurz restaked the area and completed a small program of soil and stream sampling south of Hanson Lake. In 2010, the area was restaked by John Chapman and KGE Management Ltd.
During 2012 through 2015, the area was examined by Stone Ridge Exploration Corp. with programs of prospecting, soil, till and rock sampling, structural analysis and a 288 line-kilometre airborne ZTEM and aeromagnetic survey being completed.
In 2018, the area was prospected and sampled by J.B. Kreft. A rock sample (UCYR-13) of trench rubble from trench RC-21 yielded 0.35 gram per tonne gold and 23.4 grams per tonne silver (Assessment Report 37667).