White Cliff Minerals has confirmed the locations of historical high-grade results for a suite of valuable minerals at its two key Canadian projects, defining multiple priority targets for early drilling after completing a maiden field work campaign.
The company says recent field reconnaissance, mapping and sampling has identified four distinct iron oxide-copper-gold (IOCG) targets at its Great Bear project and multiple styles of copper mineralisation at the Rae play.
At Great Bear – where the company says “vast visual copper mineralisation” has been observed – more than 175 samples were collected from the greater area where four IOCG targets were explored at Glacier, Cleaver, Thompson and Spud Bay. The Glacier target exhibits copper mineralisation in chalcopyrite-bornite-cemented breccias and in veining associated with strong potassic alteration through more than 1100m of identified strike length.
Disseminated chalcopyrite along a 10m thickness and 60m of strike was identified at the far east end of the trend in potassic-altered andesites.
At Cleaver, widespread, fresh chalcopyrite mineralisation was found to cover an area measuring about 785m by 460m, accompanied by strong radiometric uranium counts at rates of up to 4000 counts per second in structurally-controlled zones of earthy haematites. The IOCG-prospective ground, which has never been drilled, sits immediately to the south of the major Cleaver Fault.
At Thompson and Spud Bay, visible uranium and cobalt were noted, with about 700m of mineralised outcrop being sampled. Native silver was also noted near Spud Bay about 500m north of the historic and appropriately-named Bonanza mine that historically produced more than 34 million ounces of silver.
The Spud Bay target area comprises two perpendicular trends of epithermal copper and zinc sulphide mineralisation associated with fractured andesites and diorites with strong potassic alteration and is also believed to be prospective for high-grade silver. The two main Spud Bay structures are mineralised through 700m of east-west strike and for 450m north-to-south.
Additional targets were identified at Sloan, Mariner and Doghead in the northern part of Great Bear, but were not visited during the phase-one work, although plans are in place for follow-up examination in the September quarter.
About 100 samples were collected from targets identified at the Rae copper-silver-gold project in Nunavut where multiple styles of copper mineralisation include broad vertical shear zones with extensive quartz veining and semi-massive to massive copper sulphides.
White Cliff Minerals managing director Troy Whittaker said: “Pleasingly, all historically identified mineralisation across the projects has been extended laterally, highlighting the scale potential at Great Bear and Rae. We are at the first and most exciting stage in the identification of what we believe are multiple, district-scale mineralised complexes at both projects. What we are seeing here is only the beginning at Great Bear.”
The company’s field work has identified several vein systems alongside sedimentary rocks hosting chalcocite and replacement-style mineralisation of native copper within vesicular basalt flow tops.
At the HALO target, mineralisation consists of quartz-carbonate-chalcocite-native copper within veins and breccia cements and chalcocite replacement along the bedding planes of sandstones. Follow-up sampling has now extended the HALO strike length to more than 800m, which is especially promising as it pushes it further out than the previously-reported extension to 440m.
Additionally, evidence of sedimentary-hosted copper mineralisation was noted at both HALO and at the CALMAL target.
The company sees potential from field evidence at CAMAL for bulk-tonnage “Red Bed” copper mineralisation, where copper-rich mineralisation of Rae Group sediments by hydrothermal fluids is recorded. The identification of high-grade, sediment-hosted copper greatly expands the prospectivity and tonnage potential of both the HALO and CALMAL targets.
Management says chalcocite-dominant, copper-rich veining exists along about 400m of strike at its Cu-TAR target and is mirrored by three other chalcocite veins and cemented copper-rich breccia zones. The veins have been sampled along strike until they are obscured by shallow cover.
At the DON target, two semi-massive chalcocite-bornite copper-rich veins were identified and strike for more than 200m. At the Kilauea target, widespread native copper has been traced through 120m.
Analytical results from the highly-successful phase-one sampling program are due back in two to three weeks for Great Bear and a further two to three weeks later for Rae.
Other work included helicopter-borne MobileMT (mobile magneto-telluric) geophysical surveys, which were completed at both the Great Bear and Rae projects for a total of 3573 line kilometres flown, with results and interpretation expected in two to three weeks.
White Cliff’s field crew has verified the Rae Group sedimentary stratigraphy and is keen to see the MobileMT results to help it map out the subsurface of the largely covered sedimentary sequence.
And almost certainly because of the glowing assemblage of high-quality targets, the company is keen to get back into the field in September once all results are to hand and compiled, to find out just what the “vast visual copper mineralisation” could really turn out to be.
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By Doug Bright
