The First Basin showing area is underlain by Devonian to Permian marine sedimentary and volcanic rocks of the Stikine Assemblage which area overlain by marine sedimentary and volcanic rocks of the Upper Triassic Stuhini Group. Lower Jurassic rock of the Hazelton groups overly the Stuhini rock.

The volcanic and sedimentary sequences were intruded by the Tertiary-Cretaceous Coast Plutonic Complex. A wide variety of intrusive phases are present including granodiorite, quartz monzonite and diorite. Small satellitic plugs from the main batholith are important for localizing mineralization.

A silicified, hematized, and pyritized (3 per cent) minor shear occurs within greywacke or lapilli tuff. The shear is 2 to 3 metres wide by 8 metres visible strike length. A trace of galena was observed. Locally intense jarositic and limonitic staining occurs. Samples yielded 0.69 gram per tonne gold and 82.63 grams per tonne silver (Assessment Report 18156).

Work History

The first work recorded on the ground was performed by Anaconda Canada Exploration Ltd for Skyline Exploration Ltd. Placer Development Ltd and Anaconda joint ventured on the Burnie 14, Reg 10 and Stanley 7 claims around 1983. This program was carried out to follow-up on a helicopter-borne geophysical survey and consisted of geological mapping and limited trenching, prospecting, reconnaissance ground geophysics and stream sediment sampling. A total of 28 heavy mineral stream sediment samples and 20 rock samples were collected during the course of this program. The trenching and the five associated rock samples and the ground geophysics were conducted over an area just west of the present Eldorado claims. Anaconda’s work defined a silver-copper-lead-zinc-iron carbonate vein showing off the present Eldorado property with anomalous copper in heavy sediments in First Basin and anomalous gold in heavy sediments in Second Basin.

In 1987, Androne Resources Ltd completed an exploration program on the Burnie 1-4 and Dan 1-3 claims. Their work was comprised of geological mapping and prospecting (139 samples), silt sampling (56 samples) and contour soil sampling (272 samples). This program identified the Grace 2 showing, a northwest-trending shear zone with silicification and pyritization with malachite and which yielded significant gold, silver and copper assays. Androne also discovered the Grace 1 showing, a similarly-trending and mineralized shear zone, also with chalcopyrite and azurite.

Pezgold Resources Corp conducted an exploration program in 1988 that was, in part, a continuation of the 1987 program that was halted due to adverse weather conditions. This program entailed grid-based soil sampling and VLF-EM surveys over the Grace showings and four trenches totalling 37 metres over the Grace 2 showing. A total of twelve chip samples were collected from two of these trenches. Results from these trenches were erratic and discouraging. The soil survey identified numerous, multi-station, but discontinuous anomalies with the strongest response in gold and base metals in the northern part of the grid (near the Grace 1 showing) and the strongest response in gold.

During 2009 through 2011, Skyline Gold Corp. completed programs of prospecting, geochemical (rock and soil) sampling, trenching, airborne and ground geophysical surveys and 23 diamond drill holes, totalling 5676 metres, on the area as the Iskut property.