The regional geological setting of the Aurex Hill area is mainly metamorphosed sedimentary rocks of various types, including schist, phyllite, argillite, limestone (marble) and quartzite of early Paleozoic age (Yukon Group). Conformable gabbro-diorite lenses and sills, of slightly later age cut the sedimentary strata, and a few narrow quartz-biotite granodiorite and quartz-feldspar porphyry sills, of probable Cretaceous age, are present locally. Granitic plutons crosscut the sedimentary rocks and gabbro sills at several locations: east of Mayo Lake, northwest of Hanson Lake and south and east of Dublin Gulch. The Roop Lake Pluton is comprised of granodiorite and granite porphyry; it is located 30 kilometres east of the Aurex property. On Aurex Hill and the surrounding area, sedimentary rocks dip gently south and are cut by early and late brittle fault zones. Most of the early faults strike northeast, generally dip steeply southeast, and contain lead-zinc-silver lodes at Keno and Galena Hill, high grade silver at the Silver King Mine, and gold-arsenic-antimony-bismuth mineralization at Aurex Hill. Most of the late faults strike northwest, dip southwest, and offset the early faults. The age of these faults is uncertain, but as they are cut by the quartz-feldspar porphyry dykes and sills at Keno Hill and Galena Hill, they are probably Cretaceous or younger.

On Aurex Hill, the Yusezyu Formation of the Hyland Group occurs and consists of a lower sequence of quartz-sericite schist, quartz-eye muscovite schist, marble, and silver phyllite. Along the valley of Corkery Creek and beyond to the south, the lower is composed of graphitic schist, phyllite, thin-bedded quartzite, argillite, quartz-mica schist, and limestone. The most distinctive members in the Yusezyu Formation are the competent calc-silicate, pyrrhotite-bearing horizons or lenses, together with the brittle typically green in colour quartz eye-muscovite schist. Both of these units are favourable hosts to mineralization. In general, the various schist, phyllite, argillite and thin-bedded quartzite in the Yusezyu Formation are structurally incompetent and unfavourable for the occurrence of mineralization. Minor gabbro sills that occur throughout these formations are favourable sites for mineralization.