The Utica property is located between elevations of 1830 and 2290 metres on the northeast side of Paddy Peak, 18 kilometres northwest of Kaslo. The property is near the headwaters of Utica Creek, a tributary of Twelve Mile Creek. The main portal (No. 4 adit) is at 1981 metres on Crown grant 4566.
The showings were discovered and staked in July 1892 by Patrick McCue. Development work during the following years was limited to the annual assessment requirements. In about 1899 a nine-month option was acquired by Messrs. Peyton and Corbin, of Spokane. Development work to that date had been carried out in 3 adit levels. In about 1900 the property was optioned to G.H. Hughes, who drove No. 4 adit. Five claims, the Utica, Alice No. 5, Andrew Jay, Rock Boulder, and Colorado (Lots 4566, 4567, 5304, 5305 and 5308 respectively) were Crown-granted to McCue in 1903. The Sol, Sol No. 1, Minerva Fr., Hercules, and Time & Tide claims (Lots 14107-14111) were apparently Crown-granted at a later date.
No further activity was reported until 1909 when the first production was recorded. The property was acquired from the McCue estate by C.F. Caldwell & associates who incorporated Utica Mines, Limited in October 1911. Operations by the company continued into 1918. Production, mainly from the East vein, was hand sorted for shipment, the milling-grade material being stockpiled. During this period the workings on Nos. 3 and 4 levels had been expanded to a total of about 1524 metres of crosscuts and drifts. The No. 7 level, 107 metres below No. 4, was driven as an exploratory crosscut for 610 metres in about 1917, however, the veins were not located. Lessees worked the property during the period 1919-23.
The owners reached an agreement with Major H.H. Armstead & associates on the formation of a new company in which Utica shareholders would receive shares in the new company. Accordingly, Utica Mines, Limited was wound up voluntarily in November 1923 and Canadian Mines Merger Company, Limited was incorporated in July 1924; the name was changed in December 1924 to Canadian Mines Merger, Limited. Exploration work resumed in the lower adit in search for the vein extensions on that level. About 305 metres of additional crosscutting was carried out before work was suspended in 1925.
Shareholder dissatisfaction with the former arrangement led to an agreement with Strobie, Forlong & associates under which a new company Utica Mines, Limited was incorporated in May 1928. Exploration work was resumed and in 1929 the West vein was encountered in the lower crosscut, but was apparently only sparsely mineralized and work ceased. The company wound up voluntarily in March 1937.
Utica Mines (1937) Limited was incorporated by the former owners and some development work was carried out during the year, and briefly by a contractor during 1938. Further development work was carried out by the company in 1940 and 1946-50. The West vein was drifted on for about 259 metres. A raise from the East vein was completed to No. 4 level in 1947. This work encountered a mineralized zone on which No. 5 sublevel was driven. Some ore was shipped from No. 7 level dump in 1950.
J.A. Cooper of Kaslo held a lease on the property from the fall of 1954 until the fall of 1957 and sections of the East vein were mined on No. 5 and No. 7 levels. Cooper, backed by New York interests incorporated Lajo Mines Limited in June 1957 to acquire the property under a long term lease. A 50 ton-per-day mill was installed and operated on a testing basis in early 1958. The mill operated again in 1960, milling about 4630 tonnes.
Standard Berylium Corporation of New York obtained a controlling interest in Lajo Mines and carried out an extensive examination of the property early in 1961. A pilot run of 820 tonnes of dump and backfill material was put through the mill. The grade of the material was: 263.9 grams per tonne silver, 0.65 per cent lead; 2.3 per cent zinc. During the fall 30 metres of drifting was done on the East vein on No. 5 level and 13 metres of winze was sunk below No. 7 level. On the surface some trenching was done on the West and Sol veins.
Peerless Canadian Explorations Limited optioned the mine and mill from Lajo in March 1963. Development work was done on No. 4 and No. 5 levels. Underground diamond drilling was done to test the East vein and surface diamond drilling in 5 holes totalling 213.3 metres was done on the Sol and Andrew J veins. The option was abandoned prior to April 1964.
Continental Consolidated Mines Ltd. optioned the property in 1965 and some geological work was reported. Silver Peak Mines Ltd. held an option on the property in 1968. Sampling and diamond drilling was reported.
Turismo Industries Ltd. in 1978 obtained an option on a 50 per cent interest in the property. The company name was changed in July 1978 to General Energy Corp. By a further agreement of June 1979 with Martin & Lilly Ltd. and Loredi Resources Ltd. the company acquired a 30 per cent interest in the mine dumps. The dumps were estimated to contain 9072 tonnes at 257.1 grams per tonne silver (VSE SMF 12/09/79, General Energy Corp.). Lessees under the name Keen Creek Developments Ltd. during 1979 mined about 1360 tonnes on the 1130-metre level on the Last Chance claim. A new adit at the 1100- metre level was driven 66 metres to the main shear; the lease was terminated. David Minerals during 1980 carried out diamond drilling on the 1100 level, drifting to a new vein discovery, and raising to the 1130 level. The milling of 5366 tonnes of dump ore at the Ainsworth mill to May 15, 1981 proved unprofitable.
Regionally, the area lies on the western margin of the Kootenay Arc, in allochthonous rocks of the Quesnel Terrane. In the vicinity of the occurrence, the Quesnel Terrane is dominated by the Upper Triassic Slocan Group, a thick sequence of deformed and metamorphosed shale, argillite, siltstone, quartzite and minor limestone. Rocks of the Slocan Group are tightly and disharmonically folded. Early minor folds are tight to isoclinal with moderate east plunging, southeast inclined axial planes and younger folds are open, southwest plunging with subhorizontal axial planes. The sedimentary sequence has been regionally metamorphosed to lower greenschist facies.
South of the occurrence, the Slocan Group has been intruded by the Middle Jurassic Nelson intrusions which comprise at least six texturally and compositionally distinct phases ranging from diorite to lamprophyre. The most dominant phase is a medium to coarse grained potassium feldspar porphyritic granite. Several feldspar porphyritic granodiorite dikes, apparently related to the Nelson intrusions, also cut the sedimentary sequence near the occurrence (Paper 1989-5).
The Utica occurrence is hosted by andalusite schist, after argillites and limestone of the Slocan Group metamorphosed by contact metamorphism of nearby Nelson intrusions. The strata generally strike northwest and dip 25 to 60 degrees northeast but locally they can be complexly folded. The metasedimentary rocks are intruded by three stocks of biotite granite, probably related to the Nelson intrusions.
The Utica consists of two subparallel brecciated veins occurring within fault zones with sinistral strike-slip movement and later normal movement. The faults strike 040 degrees, dip between 60 and 70 degrees southeast and have well-defined walls marked by thick seams of carbonaceous gouge. It is suspected that the two faults, which are 35 metres apart in the No. 4 adit, merge toward the surface. The East vein varies in thickness from tens of centimetres up to 2 metres. It has been stoped in the No. 4 adit for a strike length of 210 metres and for 80 metres updip above that level. It contains mostly brecciated hostrocks cemented by siderite, quartz and calcite. The ore occurs as scattered lenses and veinlets of interbanded argentiferous galena and sphalerite with gangue minerals, averaging 70 centimetres in width. Tetrahedrite, arsenopyrite, pyrite, chalcopyrite, and native silver occur in minor amounts within the sphalerite-rich layers.
The west vein varies from 1 to 6 metres and is largely composed of crushed and sheared wallrock. The ore occurs in parallel shoots aligned across the vein and apparently associated with crossfractures. Silver appears to be associated with sphalerite. Late movements in the faults induced fracturing of sphalerite and shearing of galena with galena flowing around fragments of sphalerite. The veins have been explored with five adits and at least 2400 metres of drifting.
Production from the Utica mine between 1909 and 1983 yielded about 30 tonnes of silver, 1551 grams of gold, 1600 kilograms of cadmium, 171 kilograms of copper, 992 tonnes of lead and 718 tonnes of zinc from 21,823 tonnes mined.
