The F-13 showing is situated east of Ecstall River on the north bank of Big Falls Creek, 63.5 kilometres west-southwest of Kitimat and 59.8 kilometres southeast of Prince Rupert.
The showing is within the Ecstall belt, a north-northwest trending, high-grade metamorphic belt bounded by the elongate mid-Cretaceous Ecstall pluton on the west and the Paleocene Quottoon pluton on the east stratified rocks of the belt are divided into four principal units: metavolcanic rocks, metasedimentary rocks, quartzite and layered gneiss.
The F-13 showing is exposed alongside a logging road that transects a 300-metre-thick section of rusty, weakly pyritic quartz-sericite schist that is interpreted as the metamorphic equivalent of a felsic tuff or rhyolite flow. Adjacent strata are hornblende-biotite-plagioclase schist that is interpreted as intermediate to mafic tuff. Within the quartz-sericite schist unit, a 50-metre-thick strongly gossanous zone hosts increased (5 per cent to 8 per cent) disseminated pyrite, four semi-massive and massive bands between 0.4 to 2.0 metre thick, and a 0.7-metre-thick band of semi-massive to massive sulphides composed of granular pyrite with minor black sphalerite and trace chalcopyrite. A chip sample through this zone assayed 0.14 per cent copper, 166 parts per million zinc and 17 parts per billion gold.
This exploration history of this prospect indicates the low level of regional exploration coverage through the Ecstall belt. The showing was discovered on Friday, August 13, 1999, during follow-up of regional stream sediment and moss-mat survey anomalies. The prospect was located along an eight-year-old logging roadcut where it is exposed as a 50-metre-long highly gossanous band, now heavily overgrown by roadside brush. While this demonstrates once again the effectiveness of stream sediment geochemistry in this belt, it also shows that logging roads in the area have not been routinely prospected.
In 2019, Kingfisher Resources Ltd. conducted a sampling program of 102 soils and 15 rocks. Soil sampling outlined elevated Zn, Ag, Pb, and As values near the historic showing and to the west. Proximal to the mineralized showing, soil sampling returned anomalous Cu and Au values. The highest soil values in this survey returned 871.75 parts per million Cu, 51.4 parts per billion Au, 435.2 parts per million Zn, 6109 parts per billion Ag, and 84.24 parts per million Pb. Prospecting was completed upslope of known mineralization and returned encouraging values including from float in a creek drainage east and north of the F13 showing. Rock sampling returned values up to 0.35 per cent Cu and 52 parts per billion Au in outcrop (sample no: 3440049) from near the F13 showing within a rusted rhyolite with strong silica-sericite alteration and 10 per cent disseminated sulfides (Assessment Report 38705).
The F-13 showing was part of a 2019 airborne VTEM survey conducted over Kingfisher's Ecstall property. The airborne survey was aimed at detection of structures and/or conductors related to potential Cu-Au-Zn-Ag VMS-style mineralization (Assessment Report 39155).
