Fireweed Metals Corp. announced it has completed a geophysical survey on its Gayna Project (zinc-lead-silver-gallium-germanium), in the Northwest Territories, Canada. Highlights: Exploration is targeting reef margin high-grade massive sulphide mineralization using a ground gravity geophysical survey; The 2022 geophysical program identified two broad areas with gravity anomalies consistent with Kipushi-style targets; The 2023 gravity survey aims to expand the gravity coverage to identify new anomalies, and to refine existing anomalies for future drill-testing.

Gayna Project (zinc-lead-silver-gallium-germanium): The Gayna prospects are hosted in dominantly carbonate sedimentary rocks of Neoproterozoic age within the Mackenzie Mountains. These carbonate units consist of a succession of shale-carbonate rocks containing calcimicrobial limestone reefs formed by stromatolites and possibly early sponges. The reefs are surrounded by comparatively deeper-water sediments intermixed with reef-derived talus, with individual reefs several hundred metres to over three kilometres in diameter and hundreds of metres in thickness.

This sharp, near-vertical interface between the reef and the surrounding sedimentary rocks is being targeted as an environment analogous to the high-grade Big Zinc Zone at the Kipushi deposit in the Democratic Republic of Congo1. Mineralization discovered at Gayna to date occurs in veins and breccias in carbonate rocks similar to Mississippi-Valley-Type (MVT) mineralization, or Irish-type Zn-Pb mineralization. Sphalerite and minor galena occur as infill within veins, vugs, and breccias along with dolomite-calcite-quartz-pyrite.

This mineralization is interpreted as the distal expression of Kipushi-style massive sulphide mineralization that may be present along the subvertical margins of the carbonate reefs. This steep reef margin geometry at Gayna was not tested by historical, sub-vertical drill holes that targeted sub-horizontal, shallowly dipping mineralization. The geophysics work from 2022 shows compelling gravity targets, and the data generated in the 2023 gravity program will guide future drilling programs to test these anomalies using inclined drillholes.

Rio Tinto completed over 28,000 m of exploration drilling at Gayna in the 1970?s to test targets identified by prospecting or soil geochemistry, and to test stratiform targets with a grid drilling approach utilizing vertical holes on a square grid with an average spacing of 600 m between holes (Map 3). Given the vertical holes and the wide historic drill grid spacing, these drill programs left the concept of subvertical bodies of massive sulphide mineralization untested. The Project was restaked by Fireweed in 2022 to test the new exploration concept that Kipushi-style, high-grade massive sulphide may be present at Gayna.

A ground gravity survey, an airborne LiDAR survey, and an orthophoto survey were carried out in 2022 to acquire high-quality geophysical data using modern technology and practices. The results of the 2022 gravity program delineated several gravity-high anomalies over the inferred position of the reef-margins. For an overview of results from the 2022 program, please refer to Fireweed news release dated November 17, 2022.

A limited 2022 rock sampling program at known showings returned samples with high zinc, silver, and lead concentrations, and also contained elevated concentrations of the critical minerals gallium (2 to 42 ppm) and germanium (9 to 99 ppm) (locations of the 8 samples shown on Map 4 and assays in Table 1). The 2022 rock sampling returned a specimen with a spectacular zinc grade of 51.2%, as well as another sample grading 73.7% lead (Photo 1). These samples, while derived from surface boulders, illustrate the potential for an undiscovered source(s) of massive sulphides with extremely high grades, comparable to Kipushi, hosted in the same reef-margin environment.

Several extensive, high magnitude lead-zinc soil anomalies present on the Project are not readily explained by the results of the historic drilling and show potential for yet undiscovered high-grade massive sulphide mineralization along the reef-margins.