The Troitsa Lake showing region is underlain, in large part, by a compositionally zoned stock of granodiorite to quartz monzonite of the Upper Triassic Bulkley Plutonic Suite which intrudes Hazelton, Skeena and Kasalka group rocks.
The showing area is regionally mapped as Lower Cretaceous Skeena Group sedimentary rock but reports indicated volcanic and intrusive rocks as host of the mineralized zone.
The area of interest is mainly underlain by andesites of the Jurassic Hazelton Group which have been intruded by the granodiorite/quartz-monzonite Upper Cretaceous Troitsa Stock. The Troitsa Lake showing is associated with a monzonite-granodiorite dike approximately 9 metres wide that has intruded Hazelton rocks. A complicated stockwork of quartz mineralized with pyrite, molybdenite, and chalcopyrite occurs with the dike. Some mineralization, especially pyrite, extends into the volcanics.
Mineralization at the Troitsa Lake showing is described as at least five closely spaced sets of quartz-pyrite-chalcopyrite veins and mineralized fractures occurring in granodiorite and altered volcanic rocks over 30 metres. The host rocks and the stockwork mineralization have been cut by at least three ages of andesitic and dioritic dikes. Previous trenching indicated average grades in the order of 0.60 per cent copper in the stockwork mineralization and values of 0.30 per cent to 0.40 per cent copper in one of the late dikes (Assessment Report 2026). Minor amounts of molybdenite were noted in some veins and fractures.
The mineralization in the area was first discovered by G. Bleiler and F. Giauque in 1966. They staked the claims then and later optioned them to Silver Standard Mines Ltd.
In 1966 and 1967, Silver Standard Mines Ltd. completed geological mapping, trenching, sampling and diamond drilling. The results were never published.
In 1968, Silver Standard Mines Ltd. drilled two diamond drillholes totaling 361.8 metres and dropped their option on the property.
In 1969, Aston Resources Ltd. optioned the property and conducted geological mapping, geochemical sampling and ground and airborne geophysical surveys.
In 1971, Aston Resources Ltd. optioned the property to Cerro Mining Company of Canada Ltd. who executed an exploration program of silt, soil, talus and rock chip sampling.
In 1973, N. G. Cawthorn completed detailed geological mapping as part of his M.Sc. Thesis for the University of British Columbia.
The claims lapsed, and were restaked in 1983 by Payday Resources Inc., who completed geochemical soil surveys.
In 1986, Payday Resources Inc. conducted a soil geochemical survey, rock sampling, and a magnetometer geophysical survey focusing on the northwest portion of the property.
In 1999 and 2000, Shawn Turford completed prospecting on the property.
In 2010, Shawn Turford and Ralph Keefe completed a small prospecting program during which they collected five rock samples along the coast of Troitsa Lake. Sample 2 assayed 1.532 per cent copper and 18.88 grams per tonne silver and Sample 1 assayed 0.5347 per cent copper and 5.42 grams per tonne silver (Assessment Report 31748). Later that year the property was optioned to Callinan Mines Ltd. who conducted a larger exploration program on the property targeting the Troitsa Main showing (093E 005).
In 2011, the property was transferred to Callinex Mines Inc., a spinoff of Callinan Mines Ltd. Callinex conducted various work on the Troitsa property until they returned the property in 2013. The only part of their work that was related to the Troitsa Lake property was the 2012 ZTEM airborne survey which covered: the Troitsa Lake (093E 003), Troitsa Main (093E 005), Troitsa Cirque (093E 009) and Troitsa East (093E 129).
Refer to Troitsa Main (093E 005) for details of the Troitsa property work history and Fab (093E 041) for related geology and property work history details of the Cole Creek property which the Troitsa property was part of from 2010 to 2013.