The Langara occurrence is one of a group of gold-silver showings which occur in a small area 10 kilometres west of the south end of Tatlayako Lake. Other showings in this group are covered by the Standard (092N 037) and Argo (092N 038) occurrences. Gold was discovered in 1911, although the area was not explored properly until the mid-1930's, and again in 1987 and 1988.
The Langara zone is located at the eastern extent of Cloud Drifter Trend an approximately 3 by 2 kilometre gold anomaly. The Langara target is centered on a diorite intrusion that is part of the Late Cretaceous to Paleocene Bendor suite, emplaced into sandstone of the Lower Cretaceous Cloud Drifter Formation. Quartz-sulfide veins are focused along northerly lithological contacts and easterly dextral-reverse faults. Hydrothermal breccia bodies lie in structural intersection domains and were the focus of hand mining activities in the 1930s.
The area lies in an area of overlap assemblage, between the northeastern margin of the Coast Plutonic Complex and the Tchaikazan fault to the northeast. It is located within a complex belt of folds and imbricated, gently southwest-dipping thrust sheets.The thrusting took place in the Late Cretaceous because the thrusts are cut by a quartz diorite intrusion dated at 68 million years by the uranium-lead method on zircon (Geological Survey of Canada Papers 88-1E, 91-2).
The area of economic interest covers several square kilometres immediately south of a creek which flows east-northeast into Ottarasko Creek. The northern part of this area is underlain by a quartz diorite intrusion (which may be related to the 68-million-year-old intrusion mentioned above). To the south of the intrusion are Lower Cretaceous siltstone, sandstone, greywacke and conglomerate These rocks contain isoclinal minor folds locally; bedding is obscure and rather irregular. The area also contains numerous, small mafic dikes.
The contact between the intrusion and the sedimentary rocks is irregular due to dyke-like projections and small stocks of quartz diorite, but generally it trends east-northeast for at least 3 kilometres. The adjacent sedimentary rocks have been strongly altered and hornfelsed by the intrusion for a width of 200 to 300 metres, and it is this zone that contains the most important mineral showings.
The hornfelsed and altered zone is characterized by silicification, pyritization and quartz veining. Fine pyrite and arsenopyrite are pervasive in trace amounts; chalcopyrite is less common. Locally oxidation has produced conspicuous limonitic zones. Quartz veins occupy fractures that cut both the quartz diorite and the sedimentary rocks. The veins are generally between 5 and 10 centimetres thick but may be up to 1.5 metres thick; some display epithermal textures. Some veins trend subparallel to the quartz diorite contact but these are much less mineralized than those that trend between northwest and north-northeast, which may be strongly mineralized with arsenopyrite and pyrite, with minor chalcopyrite and rare malachite.
The Langara occurrence is centred on 2 short adits which were cut (in 1935) to follow mineralized quartz-filled fractures in quartz diorite, close to its contact with silicified and hornfelsed greywacke and argillite (Minister of Mines Annual Reports 1934, 1935). The diorite is sericitized. Also present is a fine-grained intrusive rock, which is a marginal phase of the diorite. The fractures strike 150 degrees and dip about 60 degrees southwest, and are traceable for 120 metres. In addition, at least one vein strikes east and dips steeply south; this is up to 0.5-metre thick and is traceable for 90 metres.
A typical average assay of chip samples taken across the widths of veins or zones in the adits that are mineralized with arsenopyrite, and pyrite is 6 grams per tonne gold and about 70 grams per tonne silver (Minister of Mines Annual Report 1934; Assessment Reports 16959, 17980). One quartz vein grab sample assayed 26.75 grams per tonne gold and 39.5 grams per tonne silver (Assessment Report 17980). Another grab sample assayed 2.52 per cent copper, 3.13 per cent zinc and 0.33 per cent lead, although high values of these metals are very sporadic (Assessment Report 16959).
In 2021, two backpack drill holes were completed and 39 grab and rock chip samples were collected at the Langara Zone (see Table 1). A total of 24 rock chip samples and two backpack drill holes were completed at a 60 metre-long trench located 150 metres east of the bedrock mineralization sampled in 2020. This trench was discovered by following up on a northeast trending line of highly anomalous soil samples that assayed between 0.66 and 5.76 grams per tonne gold. Hand trenching exposed a continuous trend of veins and breccia that grades up to 38.6 grams per tonne gold, 212.0 grams per tonne silver, 0.55 per cent copper, and 357.8 parts per million tellurium in rock chip samples. Backpack hole BP-LG-21-09 tested veins within the hand trench and returned a highlight interval of 8.42 grams per tonne gold, 49.3 grams per tonne silver and 115 parts per million tellurium over 1 metres (Press Release, Kingfisher Metals Corp., March 9, 2022).
The remaining rock samples collected in 2021 are located north, northeast, and west of the area of 2020 rock sampling. Prospecting at Langara identified an undocumented historical adit, with dump samples grading up to 9.57 grams per tonne gold, 54.9 grams per tonne silver, and 8.7 parts per million tellurium. Southwest of this adit, a grab sample grading 60.4 grams per tonne gold, 97.1 grams per tonne silver, and 0.21 per cent copper was collected, which doubles the 2020 and historical gold grades from the Langara Zone in rocks (Press Release, Kingfisher Metals Corp., March 9, 2022).
Previous assay results from 2020 work at Langara can be found in the Kingfisher Metals' Press Release dated April 14, 2021.
Refer to Cloud Drifter (new MINFILE in 2021) for common geological and work history details.
