Deposit Type:

There is potential for two types of deposits on the Sping property. These are sediment hosted Cu-Ag deposits and Eskay Creek type deposits. Sediment-hosted Cu-Ag deposits, which include Kuperschiefer type deposits, consist of stratabound disseminations of copper minerals in a variety of sedimentary rocks that include limestone and sandstone. Limestone may be associated with volcanic rocks. These deposits are typically conformable with bedding and tabular with varying dimensions. Lateral or vertical zoning from a copper rich core to peripheral lead-zinc is common. Sulphide minerals occur as disseminations or as intergranular cement. Grown faults may provide local control. Geochemically these deposits exhibit elevated values of copper, lead, zinc and cadmium. Sometimes mercury is also elevated (Lefebure, et al, 1996).

The known mineralization on the Sping property fits well into this model. The second type of deposit for which there is potential is the subaequeous Hot Spring Au-Ag or Eskay Creek type deposit. These deposits consist of vein, replacement and synsedimentary bedded sulphides in volcanic rocks and associated sedimentary strata. They are developed in active volcanic arcs. The age of these deposits is typically Jurassic. Mineralization occurs within intermediate to felsic flows and tuffs. The form of this type of deposit is highly variable. Sulphide minerals present include sphalerite, tetrahedrite, galena, chalcopyrite, native gold and silver, pyrite and arsenopyrite (Alldrick, 1995).

Mineralization:

Copper-silver mineralization occurs in a fine-grained limestone over an area measuring approximately 200 by 300 metres. This mineralization has been intersected in several drill holes to an average depth of 39 metres. Based on the 1973 diamond drill program Canadian Superior calculated a preliminary non-compliant NI 43-101 resource of 5,000,000 tons (4,500,000 tonnes) grading 0.5% Cu and 0.35 opt Ag (11.9 gpt Ag). Two surface chip samples collected from this zone during the 2007 field program returned assays of 0.345% Cu across 3.0 metres and 1.06% Cu, 52 gpt Au and 1.52 opt Ag across 2.0 metres. These values correspond well with the postulated grade of the deposit. Grab samples from the same area assayed from 0.35-0.64% Cu. This mineralization consists of fine-grained chalcopyrite and pyrite disseminated through the rock. Bornite is also present in trace to very minor amounts. These sulphide minerals are also associated with dolomitic veinlets and stylolitic seams that cross-cut the limestone (Ryznar, 1986). On surface much of the sulphide copper mineralization has been oxidized to malachite. Canadian Superior also noted the presence of leadzinc- copper in areas of unmineralized limestone (Rae, 1973). The mineralized limestone unit appears to terminate to the west by a fault. Three holes drilled along the eastern margin of the limestone outcroppings intersected unmineralized to very weakly mineralized tuffaceous rocks and clastic sediments. Mineralized surface samples collected by the author and previous work south of the 1973 drilling area suggest that the mineralized zone may extend a short distance to the south. In drill hole 73-3, minor sporadic copper mineralization was intersected in tuffaceous rocks. Also the stratigraphy intersected in this hole is interpreted to have a strong correlation with the stratigraphy that hosts the Eskay Creek deposit (Ryznar, 1994). In this regard there may be potential for this type of mineralization on the Sping property. Eskay Creek type deposits can be described as polymetallic VMS deposits that are high in precious metal content and have highly anomalous levels of mercury, antimony and arsenic. They are generally associated with a basalt-rhyolite volcanic suite (Mortenson, et al, 2003).

Elsewhere, minor amounts of malachite were observed in talus over a relatively large area in two locations in the northeast corner of the property. Trace to minor amounts of malachite and chalcopyrite were found in outcrop along fractures and shears in volcanic lava. Some malachite was also associated with quartz stringers. Assays for grab samples collected from these areas varied from 0.02-0.35% Cu.

Exploration:

During the 2007 field program reconnaissance mapping at a scale of 1:10,000 was completed on the property. Above tree line exposures are excellent whereas below tree line exposures are small and scarce making geological interpretations difficult for this portion of the property. In addition reconnaissance soil sampling was also done. .All of the soil samples were analyzed by multi-element MS-ICP methods. Metals of particular interest were copper, silver, gold, lead, zinc, cadmium, barium, and mercury.

Of particular interest is a very strong coincident lead-zinc-silver-mercury anomaly located south of the main showing area. This anomaly is approximately 750 metres long. Anomalous values for copper and barium were also obtained, although not over the entire anomalous area. Values up to 5760 ppm Zn, 318 ppm Pb, and 9.98 ppm Ag were obtained in soil samples. Also present area some elevated gold values. The significance of this anomaly is unknown. It may reflect the presence of another mineralized limestone band or it may be indicative of Eskay Creek type mineralization. In the northeast corner of the property, where sporadic copper mineralization was observed, there are a number of anomalous and high gold values. Also there are elevated copper values upslope from a locality where widespread but sporadic copper mineralization was observed in float. Two anomalous copper-silver values were obtained in soil, approximately 500 metres west of the main mineralized zone. Anomalous values for barium were obtained downslope from the main mineralized zone. High barium values may indicate the presence of limestone as the host limestone unit does contain minor amounts of barite. 

(2007 Exploration assessment report)

 

 

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