The Ferguson occurrence or Ingenika mine is located approximately 1.5 kilometres south of the Ingenika River and 106 kilometres north-northeast of the community of Germansen Landing, or about 195 kilometres northwest of Mackenzie.
The area is underlain by carbonate strata belonging to the Cambrian to Ordovician Kechika Group, which overlie sandstones of the Neoproterozoic Ingenika Group. The Kechika Group forms the core of a broad north-plunging syncline that outcrops approximately 3 kilometres south of the Swannell River.
The Ferguson occurrence or Ingenika mine setting is thought to be a replacement-type Manto deposit. Hostrocks are blue-grey to cream coloured crystalline limestone belonging to the Ingenika Group. Bedding strikes 100 degrees and dips between 20 and 40 degrees to the north. Mineralization is hosted in a carbonate-rich section of Ingenika Group carbonaceous siltstone interbedded with Kechika Group limestone-dolomite beds. Unlike the Onward (094C 003) and Onward South (094C 182) showings to the south, mineralization at the Ingenika mine does not crosscut the host limestone. Near the showings, the limestones are locally highly contorted and schistose, containing considerable sericite. Regionally, the property appears to be near the nose of a north-plunging drag fold on the west limb of a major anticline that has been overturned to the west.
The limestone is highly silicified in the area of the showings and shows "all gradations from relatively pure limestone to white quartz rock" (Geological Survey of Canada Memoir 274, page 205). Bedding-controlled siderite is also present in the mineralized areas so that the rock consists of parallel laminae of 0.25 to 5 centimetre thick white quartz, separated by layers of dense, brown siderite. Locally, the siderite is not confined to bedding planes but forms large, irregular masses up to 6 metres in diameter of coarsely crystalline, nearly pure material. Metallic minerals consist of bedding-controlled pyrite, sphalerite, and galena with less important copper and silver sulphide minerals. In addition, mineralographic study has identified arsenopyrite, pyrrhotite, magnetite, chalcopyrite, tetrahedrite, and pyrargyrite. Sphalerite and galena are the most abundant sulphides, constituting more than 90 per cent of the metallic minerals. Pyrite is locally abundant, in layers up to 60 centimetres thick, commonly overlying the base metal sulphides (Geological Survey of Canada Memoir 274, page 206).
Mineralization ranges from 1 to 3 metres thick and is present in four mineralized horizons. The Number 1 zone is the lowest, composed of stratiform but discontinuous, lens-shaped bodies of siderite, sphalerite, and galena up to 1.2 metres thick. The Number 2 and 3 zones are the most significant deposits; they sit 9 metres above the Number 1 zone. These two zones form parallel bands 90 centimetres to 3 metres wide, separated by 30 centimetres to 2.4 metres of poorly mineralized rock. The Number 4 zone is 7.5 metres above the Number 3 and reaches 2.4 metres maximum thickness. Levels 1, 2 and 4 intersected strong mineralization in the limestone host whereas level 5, the lowest level, was driven through the limestone host into barren schist.
The property has been developed by four adits and a raise totalling more than 550 metres, over 4000 metres of diamond drilling, and extensive trenching.
In 1917, the original claims in the area were staked by S. Ferguson. The claims covered an oxidized limestone hill, now known as Ferguson Hill, immediately north of Delkluz Lake and south of the Ingenika River.
In 1926, the claims were acquired by the Selkirk Mining Syndicate of Victoria. In 1927, W.R. Wilson and sons formed Ingenika Mines Limited to further develop the property and between 1927 and 1932, the company completed the development of underground drifts, crosscuts and raises, still in existence today. Extensive trenching and minor diamond drilling was also completed during this time. The underground workings explored four base metal zones from four levels (1, 2, 4 and 5) and ore was encountered in all levels except the lowest (5). Due to a lack of economic mineralization, operations ceased in 1932.
The Consolidated Mining and Smelting Company of Canada Limited (Cominco) acquired the property, then known as the Gen property, in the 1950s. From 1956 to 1957, Consolidated Mining and Smelting completed geological mapping, geophysical surveying, geochemical soil testing, trenching and tunnel rehabilitation and 3602 metres of AQ-size diamond drilling in and around the Ingenika mine, Onward (094C 003), Onward South (094C 182) and Swannell (094C 005) showings.
In 1969, Dorita Silver Mines acquired the property and completed surface and underground mapping and 21 diamond-drill holes totalling 550 metres. Based on this work, Dorita Silver Mines gave an unofficial estimated mine reserve of 22,677 tonnes grading 119.9 grams per tonne silver, 9.87 per cent lead and 6.1 per cent zinc (Assessment Report 28461).
In 1987, Cossack Gold Corporation acquired a group of 23 claims in the immediate vicinity of the historic Ingenika mine and attempted to find a purchaser for the property. The property, minus the three Teck-owned claims covering the Ingenika mine, was acquired by International Impala Resources in 1990. Impala Resources completed 22 kilometres of magnetic and very low-frequency electromagnetic geophysical surveying and 7 kilometres of induced polarization geophysical surveying. In total, 490 soil samples and 14 rock samples were collected and sent for analysis.
Cross Lake Minerals Limited restaked the Ingenika property in 2000. The new Ingenika property surrounded but did not include the historic Ingenika mine site, located on three claims held by Teck. In 2001, Cross Lake completed extensive geochemical surveys and three BQTK-size diamond-drill holes totalling 400.8 metres. The following year, Cross Lake completed four trenches totalling 175 metres and four NQTK-size diamond-drill holes. In 2004, Cross Lake Minerals granted Bard Ventures Limited a 50 per cent option on the Ingenika and Swannell properties, based on a $2.1 million expenditure by December 31, 2007. That year, Cross Lake completed 17 kilometres of three-dimensional inversion induced polarization surveying over Grid A, located in and around the Ingenika mine and covering the Ferguson and Onward South showings. The purpose of the survey was to test the geophysical method over a known occurrence. The survey over Grid A yielded positive results and a 49.5 line-kilometre survey was completed over Grid B. Grid B was located south of Delkluz Lake and covered both the Onward and Onward South showings. In 2005, Cross Lake Minerals assigned the two properties to its subsidiary, Selkirk Holdings. That year, seven diamond-drill holes totalling 992.67 metres were completed on targets identified from the three-dimensional inversion induced polarization survey. The three-dimensional induced polarization survey failed to detect any new mineralization because no major sulphide bodies were intersected during drilling, though minor pyrite and pyrrhotite was seen in and adjacent to quartz-carbonate veins.
One intersection from the Cominco 1957 diamond drill program yielded 15 per cent lead, 7.5 per cent zinc and 240.8 grams per tonne silver over 2.4 metres (Property File - E. Bronlund, 1958). Ore reserves in 1969 (Dorita Silver Mines Report and Balance Sheet, 30/11/69, Mineral Policy Sector Corporation files) were 22,677 tonnes grading 119.9 grams per tonne silver, 9.8 per cent lead and 6.1 per cent zinc. No production from this deposit has ever been recorded.
