The Eaglehead deposit is located about 50 kilometres east of the community of Dease Lake.
The area is underlain by Early Jurassic biotite-hornblende granodiorite and hornblende-biotite granodiorite in sheared contact with Lower Jurassic Inklin Formation (Laberge Group) sedimentary rocks. The granitic rocks also intrude a sequence of rocks comprising Upper Triassic Sinwa Formation (Stuhini Group) limestone and Upper Permian to Lower Triassic Kutcho assemblage mafic volcanics and sediments. Inklin Formation rocks comprise well-bedded greywacke, conglomerate and siltstone. The thinly bedded limestone of the Sinwa Formation is interbedded with the clastic rocks and can be traced along a considerable strike length. The sediments dip steeply and are folded about northwest axes. There is some evidence for overturned strata and the folds may be inclined and locally recumbent.
The Sinwa Formation has recently been assigned to the Stuhini Group (Stikine Terrane) and the Inklin Formation to the Laberge Group (Overlap Assemblage). Also see Kutcho Creek (104I 060) for details on the new age date for the Kutcho assemblage.
The intrusive rocks are foliated in restricted zones within a hundred metres of the contact with the sedimentary rocks. The sediments are only weakly foliated and display a phyllic parting that roughly parallels the bedding and the trend of the contact. Foliation in the intrusive rocks shows considerable variation in intensity and width across which it is developed. Schistose zones are commonly 0.3 to 1.5 metres wide but may be up to 10 metres in width and are interspersed between bands of less intensely foliated rock and screens of weakly fractured or jointed rock. Cataclastic textures are obvious in thin sections; the schistose rocks are regarded as mylonites.
Mineralization is mainly hosted in altered biotite-hornblende granodiorite and hornblende-biotite granodiorite which are cut by numerous porphyry and feldspar porphyry dikes. The most widespread alteration is retrograde metamorphism in cataclastic zones forming a propylitic or greenschist facies assemblage consisting of quartz, chlorite, sericite, albitized plagioclase and lesser carbonate, epidote and hematite. Elsewhere, the less sheared rocks are bleached to a cream or buff colour. In these leucocratic zones, the least altered rocks have fine-grained sericite clouding the feldspars and contain scattered grains of chlorite, epidote, and rhombs of ankeritic carbonate. The more strongly altered zones are phyllic assemblages of coarse-grained sericite (determined by X-ray to be muscovite), quartz, and ankeritic carbonate as veins and fracture fillings. Quartz veins are generally small, widely spaced, and often are barren, milky white quartz.
Six mineralized areas (West, Camp, Pass, Bornite, East and Far East zones), occur along a linear zone over 8600 metres long and 800 metres wide. Mineralization appears to be concentrated in steeply dipping shear zones, especially those containing chlorite, and consists of chalcopyrite, bornite, molybdenite and pyrite. Malachite is widespread and chalcopyrite and pyrite are ubiquitous. Pyrite content in places approaches 3 to 4 per cent but there is generally 1 per cent or less. Chalcopyrite occurs as disseminated grains but also occurs in coarse patches in gash veins, stringers and irregular fractures. In many mineralized fractures chalcopyrite is accompanied by potassium feldspar flooding in otherwise propylitic altered rocks. Pyrite or hematite and specularite sheared along slip faces is common; some chalcopyrite-bearing fractures transect foliation. Molybdenite is evident in quartz veinlets. Small amounts of chalcocite as rims on chalcopyrite, chrysocolla and tetrahedrite occur locally. Minor cuprite and native copper were also observed in drill core.
Approximate reserves are 30 million tonnes grading 0.41 per cent copper, 0.01 per cent molybdenum, 2.71 grams per tonne silver and 0.2 gram per tonne gold (CIM Special Volume 37, page 182).
In 1963, Kennco Explorations Ltd. staked the Joy claims on the showing. From 1963 to 1965, Kennco conducted geochemical surveys, trenching, induced polarization (IP) surveys and 4 diamond-drill holes. In 1970, the claims were re-staked as the Eagle 1-22 claims by Spartan Exploration Ltd. In 1971, Esso Resources Canada (Imperial Oil Enterprises) optioned the property and staked additional claims. From 1971 to 1974, Esso completed geological mapping, geochemical soil and silt surveys, IP and magnetometer surveys and 25 diamond-drill holes. In 1975-76, Imperial completed geochemical soil surveys, IP surveys and 5 diamond-drill holes. Between 1979 and 1982, Nuspar Resources Ltd. (formerly Spartan) completed airborne magnetometer and electromagnetic surveys, IP surveys, geochemical surveys and 5847 metres of diamond drilling. Esso re-assumed control of the property in 1982 and completed a compilation of all exploration data from 1971 to 1982.
In 1989, Homestake Canada Ltd. acquired Esso's interest in the property and completed small geochemical surveys in 1991 and 1992.
The main core of the claim units, the Eagle 8 (18 units) were only allowed to expire by 2001. In 2002, J. Poloni staked the open property and then conducted a program consisting of grid establishment, rock sampling, drill core examination and sampling. In 2004, J. Poloni completed a soil survey and struck an agreement with Carmax Explorations Ltd. to carry out further exploration in 2005. In 2005, Carmax Explorations Ltd completed a 25 kilometre IP survey over the eastern extension of a 10-kilometre-long zone of porphyry mineralization. The most easterly of 59 holes drilled during previous exploration between 1970 and 1981 intersected 0.94 per cent copper over 63 metres (as reported in Exploration and Mining in British Columbia 2005). Drilling is planned in 2006 to investigate this high-grade intercept and, in the Far East zone, to test IP and soil anomalies. In 2006, a total of 3095.3 metres of drilling was completed in ten holes. The 2007 work program consisted of road improvement from the Turnagain River, establishment of a new survey grid (43.8 kilometres), 3-D IP over the new grid with overlap of old geophysics, soil geochemistry over the new grid (139 samples), camp enlargement, and diamond drilling of 4090 metres in twelve holes. The 2008 work program consisted of road improvement, including the installation of 13 culverts; repairs to the collapsed Weatherhaven tents, the purchase and installation of an additional Weatherhaven tent, set up of six additional tents for work crews, the geochemical surveying of drillhole EH#30-35; the diamond drilling of 5495 metres of NQ core in fourteen holes, and the initiation of road and drill site reclamation. Drillholes #82 to #89, #92, and #94 were completed in the East zone area, holes #90-#91 being located to the west between the East and Bornite zones, and #95 being drilled in the Far East area on the new 3-D IP anomaly established in 2007.
In 2012, Carmax Mining Corp. released an updated inferred mineral resource of 102.5 million tonnes grading 0.29 per cent copper, 0.010 per cent molybdenum, 1.9 grams per tonne silver and 0.08 gram per tonne gold in the East and Bornite zones (News Release - Carmax Mining Corp., May 16, 2012).
In 2014, Carmax Mining Corp. resumed exploration and completed 2264 metres of diamond drilling in four holes, a Titan-24 ground geophysical survey (18.0-line kilometres), a combined airborne magnetic and radiometric survey (787-line kilometres), re-logging 18 historical drill core (5747 metres), and collected samples for a preliminary rock characterization study.
In 2015, the Eaglehead project is owned by Copper Fox Metals Inc. and Carmax Mining Corp. Efforts were focussed mainly at the Pass zone located northwest of the Bornite and East zone mineral resource areas. The work program included two exploration drillholes and re-logging of nine historic drillholes. Drilling totalled 1182 metres and targeted Titan-24 high chargeability anomalies. Copper-molybdenum-gold and silver mineralization at the Pass zone occur within strong potassic and phyillic altered intermediate intrusive rocks. Carmax completed 2 NQ diameter diamond-drill holes (1184.4 metres), re-logged, sampled and re-sampled ten historical diamond drillholes (2103.8 metres); preliminary metallurgical characterization of the copper mineralization from the Eaglehead deposit and constructed 600 metres of new road/trail.
Work in 2016 by Carmax Mining Corp. consisted of relogging historic core from 40 diamond-drill holes and sampling or re-sampling of this core. All available sample pulps (approximately 15,000) were reanalyzed to standardize sample digestion and analytical methods and to determine the silver content of the mineralization. Diamond drill core samples of mineralized zones and non-mineralized zones were also selected for measurement of chargeability and resistivity. Results were to be used to model Titan-24 geophysical survey responses. In December of 2016, Carmax announced positive results from grindability and flotation testing performed on mineralized samples (Information Circular 2017-1, page 166).
During 2018, District Copper Corp. (formerly Carmax Mining Corp.) completed a field program that included: i) re-logging 36 historical diamond-drill holes (7789 metres); ii) sampling and re-sampling on 19 historical diamond-drill holes (917 samples) for copper, molybdenum, gold, silver and a suite of trace elements; iii) recovery of additional historical diamond drill core from the Camp zone; and iv) re-visiting previously mapped outcrops as part of a compilation reconnaissance program to obtain alteration data and determine controls on the copper mineralization on a portion of the Eaglehead intrusion underlying the Camp zone and the area north of the Camp and Pass zones (approximately 3 by 2 kilometres).