The Poco occurrence, located 3 kilometers northeast of Mount Burden and 95 kilometres north of the town of MacKenzie, occurs in Ancestral North America terrane Paleozoic platformal carbonates.
Ordovician Skoki Formation, Silurian Nonda Formation, Silurian to Devonian Muncho-McConnell Formation and Lower and Middle Devonian Stone Formation and Middle Devonian Dunedin Formation carbonates, overlain by Devonian and Carboniferous Besa River Formation limy shale and Lower Carboniferous Prophet Formation cherty dolomite, are exposed in a folded thrust plate east of Mount Burden. West of Mount Burden, Cambro-Ordovician Kechika Group clastics and carbonates, Ordovician Skoki Formation and Nonda Formation carbonates comprise the Mount Burden anticlinorium. Hanging wall strata, above the prominent Mount Burden thrust, dip to the east and southeast and are locally folded. The Mount Burden thrust juxtaposes the Silurian Nonda Formation with the Devonian and Carboniferous Besa River Formation.
The Poco Main, Poco North, West Rusty and East Rusty zones comprise the Poco occurrence, a widespread lead and zinc showing. Galena occurs as veins and is disseminated with sphalerite in Devonian reefal dolomite breccias. Hydrozincite is common in the dolomites. A continuous chip sample from the West Rusty zone averaged 8.5 per cent zinc and 3.2 per cent lead over 12.5 metres; a three-metre chip from a trench on the Poco Main showing assayed 13.8 per cent zinc and 5.5 per cent lead (Assessment Report 5745). A five-hole drill program in 1975 failed to intersect significant grades.
In 1993, Noranda Exploration Company Ltd. conducted geological mapping and prospecting over the Poco Ridge area. Mineralization observed was found to be stratabound within the dolomitized Upper Stone Formation. Sphalerite, galena, hydrozincite, coarse grained dolomite, quartz, barite?, bitumen, and minor malachite occur as disseminations, veins, open-spaced fillings and solution breccias exposed within north-south, northeast-southwest, east-west and east-northeast structural zones up to 25 metres wide. These structural zones form a larger north-south trending mineralized area which measures approximately 700 metres in length. Chip samples taken across these mineralized zones returned values of 13.0 per cent Pb, 6.1 per cent Zn over 10.5 metres (Main Zone); 13.0 per cent Zn over 2.0 metres (Main Zone); 4.5 per cent Zn over 4.0 metres ((South Central Zone) and 5.87 per cent Pb, 11.26 per cent Zn over 3.0 metres (North Central Zone).
Approximately 400 metres to the south of the Main Zone exists a 250 metre long boulder train consisting of dolomite, quartz solution breccia boulders to 2.0 metres in diameter which contain medium grained open-space filled galena crystals and hydrozincite on fractures. This boulder train was observed to parallel the strike of the main lithologies in an area of no outcrop and may represent the southerly extension of the mineralized Upper Stone Formation. Grab samples from this area returned up to 11.65 per cent Pb and 5.35 per cent Zn (Assessment Report 23032).
The Minfocus Exploration Corp. 2015-2016 fieldwork, and research enabled by that work, plus the LiDAR survey in late 2017, have together added substantially to the knowledge (showings, soil and stream-sediment surveys) accumulated in the three earlier phases of exploration at the Coral property, which includes the Poco occurrences. Widespread zinc values seen across the Coral property include: rock samples on Poco Ridge, soil anomaly, two showings and sphalerite ± galena in drill core at Hound Dog Creek, and strong, extensive stream-sediment anomaly in Tangle Creek.
Refer to CORAL 094B 008, situated 3 kilometres south of Poco, for further relevant area information.
