Cobalt – Las Aguilas
Direction and Depth: Significant mineralization and geology.
San Roque is on the northern edge of the Somoncura Massif, a crustal-scale, broad uplifted zone consisting of a metamorphic basement of Precambrian to Paleozoic rocks overlain by Jurassic, Cretaceous, and Tertiary volcanic to sedimentary rocks, capped by Quaternary basalts. Units of all ages except the capping basalts are known to host mineralization at San Roque.
Within the Marifil formation, four gold zones have been mapped on the property . This formation is a sequence of Jurassic volcanic sediment underlain with metamorphic basement sediments.
The youngest rocks in the area of mapping are post-mineral conglomerates and sandstones of the Cretaceous Roca Formation. These rocks, often containing marine fossils, form minor, thin outcrops throughout the map area.
Gold, silver, lead, zinc and indium mineralization are hosted within two styles of vein systems. These zones are relatively broad and gently dipping.
This mineralization is associated with pyrite, galena, sphalerite in veins, veinlets, breccia-related dissemination. Chalcopyrite occurs only as disseminated grains in wallrock, and a quartz-alunite-gold association is reported in veins and veinlets. Extended intervals of drilling return grades of gold (0.1-0.5 gpt), silver (1-20 gpt), Pb (0.1- 0.3 %) and Zn (0.1-0.5%) with indium varying from nil to 600 gpt. Most drill holes were terminated in mineralization because the importance of low-grade disseminated or fine stockwork mineralization has been under-appreciated until recently. To date, mineralization is open in every direction and at depth.
The Property can be accessed from the community of Trout Lake by driving southeast on Highway 31, then turning east onto one of three Forest Service Roads that become ATV trails leading to the alpine. Rudabue (Burg Creek) road provides ATV access to the northwest corner of the Property from which hiking trails can be used to reach some of the northern occurrences (Morning Star, Chance, IXL, Noble Five); Rady Creek road provides ATV access to the central part of the Property (Foggy Day area); American Creek road provides ATV access to the southern part of the Property (Bonanza, Butte and Gallant Boy). Access to other areas of the Property is by helicopter and/or by foot.
The Property is underlain by lower Paleozoic eugeoclinal strata of the Lardeau Group (Fyles and Eastwood, 1962). It is subdivided into six formations (Index, Triune, Ajax, Sharon Creek, Jowett and Broadview) of which the lowermost (Index) and uppermost (Broadview) are the most widespread. The Triune (siliceous argillite), Ajax (quartzite) and Sharon Creek (siliceous argillite) formations are restricted to the Trout Lake area. The Jowett Formation is a more widespread mafic volcanic unit. The thick sequence is isoclinally folded and intensely deformed, but only weakly metamorphosed.
In the district, the most productive veins occur along or near the northwest-trending axial trace of the Silver Cup anticline and close by in subsidiary fold apices that are accompanied by faults and/or shear zones. The main foliation strikes northwest and dips moderately to steeply northeast.
Mineralization does not appear to be spatially or temporally related to intrusive rocks which are rare in the area. Small dykes and stocks of gabbro and slivers of ultramafic rock do occur along the axial trace of the Silver Cup anticline south of Triune Mountain; their genetic association with mineralization, if any, is not known.
Veins on the property developed within phyllitic to graphitic argillites, slatey to siliceous argillites, siltstones and greenstones in association with faults, shear zones, and occasionally joint sets. They typically trend north-northwest to north-northeast and dip steeply east; however, some mineralized veins have other orientations. They are commonly moderately discordant with respect to the prominent foliation in the host rocks. The resulting veins are vertically and laterally persistent and range in width from centimeter-scale to occasionally more than 5m and can be subject to structural thickening.
Mineralization primarily occurs within discrete veins of white to semi-translucent, massive to drusy quartz with variable amounts of cream ankerite that, upon exposure to the elements, weathers orange-red. Pyrite is typically present in at least trace amounts, but zones of semi-massive to massive pyrite can occur (e.g. Bonanza). The base metal sulphides galena, sphalerite, chalcopyrite, tetrahedrite and chalcocite typically occur in trace amounts, but can form semi-massive to massive seams in richer veins (e.g. Morning Star. IXL, Chance). High concentrations of lead+/-zinc are commonly associated with elevated gold and silver grades (e.g. Foggy Day). Narrow iron-carbonate alteration envelopes are common and are particularly well-developed adjacent to veins enclosed in phyllitic volcanic rocks and to a lesser extent in veins cutting argillites, siltstones and sandstones. Secondary pyrite was noted in the siliceous, slatey argillites that are in contact with some veins located closer to the Silver Cup anticline and is suggestive of the presence of quartz-sericite-pyrite wallrock alteration.
Prominent iron-carbonate zones with variable amounts of quartz veining may also be important hosts to polymetallic mineralization (e.g. Gallant Boy).
Significant cobalt values have recently been confirmed to be hosted in the ultramafic intrusions. Recently cobalt and nickel values have been found to occur in an ultramafic intrusion where a sample gave only low gold and silver values but assayed 0.20% cobalt and 0.30% nickel.
Work in 2020 by Spey Resources
Work by Spey Resources in 2020 consisted of locating and sampling mineralization from the IXL, Morning Star, Chance, Foggy Day, Bonanza, Butte and Gallant Boy workings as well as a number of other prospects on the Property. The samples have been submitted for analysis and the resulting data will be reported in due course.