The Leadville (Lucky Todd-Comstock) occurrence is located at an elevation of approximately 1650 metres on an east-facing slope of Iron Mountain, approximately 8.5 kilometres south-southeast of Merritt.

The area lies completely within the western belt of the Upper Triassic Nicola Group. This northeast-trending belt represents the youngest Nicola Group rocks, consisting mainly of an east-facing sequence of calc-alkaline flows that grade upward into pyroclastic rocks, epiclastic sediments and limestone.

In the vicinity of the Leadville deposit are brown to pink potassium feldspar-rich dacitic to rhyolitic flows and flow breccias, and white to green rhyolite. Primary flow structures strike north-northwest and dip very steeply eastward. These units are interbedded with amygdaloidal andesite agglomerate, lapilli to ash flow tuff and andesitic to dacitic breccia.

The regional fault system defining the Nicola Group belts strike north to northeast. A major northeast-trending fault is mapped on Iron Mountain. Nicola Group volcanic and sedimentary rocks are intruded to the north by Lower Jurassic granitic batholiths; diorite outcrops are evident.

The felsic units host galena and sphalerite mineralization in barite veins. The Leadville shaft was sunk on a zone of banded veins and bedded lead-zinc-barite in sheared, flow-banded potassic rhyolite. The shear zone strikes 025 degrees and dips 80 degrees west. The mineralized zone is more than 50 metres long and less than 1 metre wide. The zone is cut off or disjointed by faulting.

Mineralization in the volcaniclastic units consists of specularite and chalcopyrite in irregular fractures that are scattered randomly in a zone 600 metres in diameter. Malachite and azurite staining is present.

Work History

In 1927 and 1928, a 32-metre shaft was developed on a north-south–striking galena-sphalerite-barite vein. In 1947, the Leadvillle shaft was rehabilitated and 33 tonnes of ore were mined yielding 2.115 kilograms of silver, 5643 kilograms of lead and 258 kilograms of zinc.

In 1951, Granby Consolidated dewatered the Leadville shaft and sampled the workings. In 1958, New Jersey Zinc completed an unknown amount of diamond drilling north of the Leadville shaft area.

In 1961, a program of trenching, stripping and sampling was performed on the Charmer (MINFILE 092ISE053) occurrence area to the south of the occurrence. In 1966, Manor Mines completed two drillholes near the Leadville shaft.

During 1968 through 1974, Acaplompo Mining and Development staked the Makelstin claims and completed programs of ground magnetic and electromagnetic surveys, airborne magnetic surveys, soil sampling and two drillholes, totalling 175.8 metres, on the area.

In 1976 and 1977, Quintana Minerals completed programs of geological mapping and rock sampling on the area as the One-Sixty-One claims. Samples from an area of altered felsic volcanics, located approximately 650 metres northeast of the Lucky Todd shaft, yielded up to 0.80 per cent copper, 0.80 per cent zinc, 0.18 per cent lead and 10.0 grams per tonne silver (Assessment Report 6248). A historical shaft of unknown age is also reported in this area.

During 1979 through 1981, Chevron Standard completed programs of soil, silt and rock sampling, a ground electromagnetic survey and geological mapping on the area.

In 1984, Kidd Creek Mines Ltd. completed a program of geochemical (rock and soil) sampling and geophysical (induced polarization and magnetic) surveys on the area. Samples from an area of trenching, located approximately 650 metres northeast of the shaft, yielded up to 0.942 per cent copper and 47.9 grams per tonne silver, while a sample taken approximately 500 metres north-northwest of the shaft yielded 0.439 per cent copper (Assessment Report 12860).

During 1983 through 1988, Aberford Resources completed programs of rock and soil sampling, trenching, geological mapping, ground and airborne geophysical surveys and nine diamond drill holes, totalling 569.9 metres, on the area immediately west of the occurrence as the Diane claims of the Stirling property.

During 1987 through 1989, Golden Dynasty Resources Ltd. completed programs of prospecting, geological mapping, geochemical (rock and soil) sampling, ground electromagnetic and magnetic surveys and four diamond drillholes, totalling 455.7 metres, on the area as the Iron Mountain property.

In 1995, Cambridge Minerals Ltd. completed an 834.0 line-kilometre airborne magnetic and electromagnetic survey on the area immediately north and east of the occurrence as the SK 1-16 claims.

In 2001, Lloyd Addie prospected and till sampled the area immediately north and east of the occurrence as the LD property.

In 2005, Del Exploration Ltd. completed a minor program of geological mapping and rock, silt and soil sampling on the area as the Rusty 1-4 claims. A sample (05TP001) of massive barite from the east side of the Lucky Todd shaft yielded greater than 1.00 per cent lead, 0.366 per cent zinc and 32.5 grams per tonne silver, whereas a sample (05WP046) from historical trenches exposing a shear zone with quartz veins and copper mineralization (chalcopyrite?), located approximately 600 metres to the northeast of the shaft, yielded greater than 1.00 per cent copper and greater than 100 grams per tonne silver (Assessment Report 27926).

In 2006, West Range Exploration Ltd. completed a program of geological mapping and rock sampling on the area as the Iron Mountain property. In 2008, Paget Minerals examined and rock sampled the area. Also in 2008, North Bluff Exploration completed a program of soil sampling and an induced polarization survey on the area to the north of the occurrence (LD – MINFILE 092ISE156).

In 2010, Navigo Ventures completed a program of geological mapping and a 22.1 line-kilometre induced polarization survey on the LD area to the north of the occurrence.

During 2013 through 2018, the area was prospected, mapped and sampled by K. Ellerbeck. In 2019, Lode Resources Inc. completed a program of soil sampling and a ground electromagnetic (VLF) survey on the area as the Comstock property. In 2014, a grab sample from the shaft area yielded 0.996 per cent lead, 0.586 per cent zinc and 11.9 grams per tonne silver (Assessment Report 34963). In 2018, a grab sample (LD18-2) from a zone of sheared quartz vein with malachite staining in an altered rhyolite, located approximately 600 metres northeast of the shaft, yielded 1.185 per cent copper, 0.202 per cent lead, 0.738 per cent zinc and 428 grams per tonne silver (Assessment Report 37588).

In 2019, Lode Resources Inc. completed a program of soil sampling, a ground electromagnetic (very low frequency) survey and seven short packsack drill holes, totalling 7.92 metres, on the area as the Comstock property.

In 2020, Freeman Gold Corp. completed a program of prospecting, geochemical (rock and soil) sampling, a 12.85 line-kilometre induced polarization survey and a 12 line-kilometre ground magnetic survey on the area as the Comstock property. Two samples (B829282 and B829283) from the Leadville adit area yielded 0.04 and 0.22 gram per tonne gold, 21.4 and 58.3 grams per tonne silver and 1.09 and 0.75 per cent lead with 0.99 and 0.89 per cent zinc (Besserer, D. [2021-05-21]: NI 43-101 Technical Report for the Comstock Property, Nicola Valley, South-Central Interior of British Columbia).