The Pedro Georgia occurrence is located at the confluence of Koris Creek and Georgie River, east of Portland Canal and 17 kilometres south of Stewart.
Regionally, the area lies adjacent to and includes moderately folded volcanic and sedimentary rocks of the Lower Jurassic Hazelton Group intruded by a succession of plutons of the Tertiary Coast Plutonic Complex. Hazelton Group rocks include a variety of sandstones, conglomerates and breccias as well as minor intercalated tuffs, siltstones and flow material. Granodiorite is the dominant rock of the Coast Plutonic Complex but stocks and plutons vary from quartz monzonite, quartz diorite to granite. Numerous dike swarms range in composition from granite, quartz monzonite, granodiorite and quartz diorite.
The Pedro Georgia property is underlain by an assemblage of sheared epiclastic rocks (lapilli tuffs) and andesitic flows of the Hazelton Group intruded by massive granodiorite and related dikes of the Hyder Pluton. The epiclastic rocks consist of angular and unsorted andesitic fragments within either a fine-grained sandstone or tuff matrix. The rocks have been locally subjected to strong shearing movements (150 degree trend with west dips) and are generally altered to a chloritic foliated rock. Calcite and epidote stringers are common. Several fault zones are evident, the most prominent, striking 340 degrees and dipping 35 degrees south, is located along Koris Creek. This pyritic fault zone is up to 6 metres wide and consists of weakly silicified volcanic rock with fragments of altered granodiorite. Sulphide-bearing quartz veins are associated with northwest-trending shears or fracture zones within Hazelton Group rocks near granodiorite intrusive rocks. The shear zones are generally occupied by sericitic to chloritic schists.
An adit follows a narrow sulphide-bearing quartz vein striking 137 degrees and dipping 65 degrees north to vertical at the confluence of Koris Creek and Georgie River. This vein represents part of the Pedro Georgia workings and varies from 1 to 40 centimetres wide. Mineralization consists of variably coarsely crystalline galena, coarse sphalerite, pyrite, minor chalcopyrite and arsenopyrite. Chlorite and calcite occurs along the shear zone. Grab samples of this vein assayed up to 0.20 gram per tonne gold and 300.97 grams per tonne silver (Assessment Report 13350).
Several adits have been developed on nearby mineralized quartz veins, some of which range to 3 metres in width. Recent exploration has re-discovered an upper and lower adit developed on a narrow shear zone containing short discontinuous quartz lenses 1 to 2 metres long and 0.5 metre wide. Sparse chalcopyrite, pyrrhotite and pyrite are evident. Grab samples of mineralized quartz vein material assayed up to 1.09 grams per tonne gold and 188.88 grams per tonne silver (Assessment Report 17705).
Granby Gold Inc. conducted airborne magnetometer and gamma ray spectrometry surveys (and geological interpretation of the same) over their East Georgie River project area, including the Pedro Georgia showing, from 2017 to 2020.
