TDG GOLD CORP.

Unlocking World-Class Copper-Gold-Silver Exploration Potential in the Toodoggone District, British Columbia

Sofia

Sofia Property Overview

The Sofia Property, located in the Toodoggone mining district of north-central British Columbia, covers approximately 93.6 km² and hosts a suite of porphyry and epithermal mineral showings analogous to those at Kemess, Shasta, and Lawyers. Now wholly owned by TDG Gold Corp. following its February 14, 2025 acquisition from QuestEx Resources Ltd. (“QuestEx”) (a wholly owned subsidiary of Skeena Gold + Copper), the project lies 30 km north of the Kemess Mine and is underlain by Takla and Hazelton Group volcanic sequences intruded by Early Jurassic Black Lake quartz-monzonite stocks. In 2022, QuestEx completed an extensive diamond drilling program comprising eleven holes totaling 4,398 m, testing both IP anomalies and mapped intrusive contacts. The work confirmed copper-gold mineralization of porphyry affinity and demonstrated vectors toward a potentially fertile intrusive center northeast of the 2022 drill area.

Geological Setting

Sofia lies within the eastern Stikine terrane, in a 100 km-long mineral belt of Hazelton Group volcanics unconformably overlying Takla and Asitka Group arc rocks. The sequence is intruded by the Black Lake Intrusive Suite—felsic to intermediate plutons and dykes dated at 193–202 Ma—genetically linked to Cu-Au-Mo porphyry systems across the Toodoggone. The property stratigraphy includes andesitic to basaltic flows and tuffs (Duncan and Metsantan members), overlain by bimodal volcanics (Junkers and Graves members). The Jock Creek Pluton, a quartz-monzonite dated at 196.7 ± 0.3 Ma, intrudes these units and locally grades into magnetite-bearing granodiorite hosting copper-gold mineralization at Sofia. Regionally, northwest-trending normal faults and northeast cross-structures control both intrusive emplacement and mineralizing fluid pathways.

Mineralization

Three principal mineralization styles occur at Sofia:

  1. Low-Sulfidation Au-Ag Epithermal Veins – Quartz-chalcedony-amethyst veins along a NW-trending, 6 km corridor (Griz–Sickle–Quartz Lake trend). Historic intercepts include up to 3.5 g/t Au and 33 g/t Ag over 11.6 m (Stealth 2004). Veins are hosted in dacitic to andesitic volcanics below an intraformational unconformity, locally enriched in Pb-Zn-Ag-Au.
  2. High-Sulfidation Au-Ag Zones – Alunite Ridge, BS Gold, and Alexandra zones define a 5 km alteration corridor of silica-alunite-illite assemblages with anomalous Au-Cu soil geochemistry (up to 0.9 g/t Au, 0.2 % Cu). These zones pre-date the low-sulfidation veins and are genetically and spatially related to underlying porphyritic intrusions dated at ~190 Ma.
  3. Porphyry Cu-Au Mineralization – The Sofia showing exposes potassic-altered quartz monzonite with quartz-magnetite-chalcopyrite veinlets and disseminated sulfides. 2007 drilling by BCGold intersected 0.22 % Cu and 0.16 g/t Au over 10 m. 2022 QuestEx holes SF-22-06 and SF-22-07 returned 100.5 m of 0.16 g/t Au and 0.14 % Cu and 117.9 m of 0.26 g/t Au and 0.21 % Cu, respectively—interpreted as peripheral porphyry mineralization within Takla basalts adjacent to Black Lake intrusives.

 

Exploration and Development History

Exploration began in the 1980s with geochemical and geophysical surveys by Peralto Resources, followed by extensive mapping, sampling, and drilling campaigns by Stealth Minerals (1999–2006) that discovered the Griz–Sickle vein systems and Sofia porphyry showing. BCGold (2007) confirmed porphyry mineralization at shallow depths. Cazador Resources (2014–2017) conducted airborne magnetics and IP surveys, and Colorado/QuestEx (2019–2022) advanced geochemical, geophysical, and drilling programs culminating in the 2022 campaign.

Significance and Potential

Drilling and lithogeochemical data from 2022 indicate Sofia lies on the fringe of a fertile porphyry Cu-Au center, likely northeast of current drilling beneath the Toodoggone River valley. Elevated manganese (600–2000 ppm), potassic alteration with secondary “shreddy” biotite, and NNE-trending vein orientations all vector toward this concealed center. Future work should include drilling northeast across the river, magnetotelluric or deep IP surveys, and testing of un-drilled resistivity highs and soil anomalies at Alexandra and south-Sofia. The district’s proximity to infrastructure (Kemess powerline and airstrip), extensive alteration, and multi-phase mineralization confirm Sofia’s importance within the evolving Toodoggone Cu-Au-Ag camp.