The Bren (Brule 3-4 and Ubble 7-10 claims) occurrence is located southwest of a creek, referred to as Bren Creek, at an elevation of approximately 1220 metres and 1.4 kilometres southwest of the northern end of Thutade Lake, about 198 kilometres north-northwest of the community of Germansen Landing. The occurrence lies on the eastern edge of the Spatsizi Plateau at the southern end of the Toodoggone Gold Camp.

Regionally, the area is situated within a Mesozoic volcanic arc assemblage, which lies along the eastern margin of the Intermontane Belt, a northwest-trending belt of Paleozoic to Paleogene sediments, volcanics and intrusions bounded to the east by the Omineca Belt and to the west and southwest by the Sustut and Bowser basins. Devonian to Permian Asitka Group crystalline limestones are the oldest rocks exposed in the region. They are commonly in thrust contact with Upper Triassic Stuhini Group andesite flows, pyroclastic rocks and marine sedimentary rocks. The Asitka and Stuhini group rocks have been intruded by the Early Jurassic granodiorite to quartz monzonite Black Lake Suite and are in turn unconformably overlain by or faulted against Lower Jurassic calc-alkaline volcanics of the Toodoggone Formation (Hazelton Group). To the west these units are overlain by sedimentary rocks of the Middle to Upper Cretaceous Sustut Group.

The dominant structures in the area are steeply dipping faults that define a prominent regional northwest structural fabric trending 140 to 170 degrees. High angle, northeast-striking faults (approximately 060 degrees) appear to truncate and displace northwest-striking faults. Collectively these faults form a boundary for variably rotated and tilted blocks underlain by monoclinal strata.

Locally, variable amounts of argentite, tetrahedrite, sphalerite, galena, pyrite, bornite and malachite mineralization occur as blebs and masses in at least four quartz-carbonate veins that parallel the limestone bedding. Veins widths vary from 5 to 121 centimetres and are reported to be stratabound.

In 1957, diamond drilling is reported to have yielded intercepts of 349.7 grams per tonne silver and 0.68 gram per tonne gold over 0.09 metre in drillhole G-6; 140.2 grams per tonne silver and 0.68 gram per tonne gold over 0.60 metre in hole G-3 and 123.1 grams per tonne silver with 0.34 gram per tonne gold over 0.6 metre in hole G-7 (Assessment Report 4200). Also, at this time, surface samples were reported to have yielded from 11,135.5 grams per tonne silver over 0.45 metre to 801.3 grams per tonne silver over 1.35 metres (Assessment Report 25003).

In 1992, a sample (4696) assayed 0.695 gram per tonne gold, 40.0 grams per tonne silver, 0.85 per cent zinc, 1.16 per cent lead and 2.3 per cent copper (Assessment Report 22721).

The area has been historically explored since the 1930s in conjunction with the nearby Firesteel occurrence (094E 002) located 1.9 kilometres to the north. During 1944 through 1946, Cominco Ltd. completed programs of prospecting, geological mapping and trenching on the area as the Bren claims.

In 1957, Granby optioned the property and completed 11 diamond-drill holes on the Bren claims.

In 1968, Granby re-optioned the claims and completed 14 surface trenches and 3 drillholes, totalling 78.3 metres. The option was dropped in 1969.

In 1972, El Paso Mining and Milling Co. completed a program of geological mapping, soil sampling, a 10.5 line kilometre gravity survey and 23.5 line kilometre electromagnetic (VLF) survey on the area as the Firesteel property.

In 1980, Serem Ltd. completed a program of soil sampling on the area. In 1985, a 6.6 line kilometre ground electromagnetic (VLF) survey was completed.

In 1992, Placer Dome Inc. completed a program of rock and soil sampling, geological mapping and ground electromagnetic, magnetic and induced polarization surveys on the area as the Cas 3 and 6-9 claims. In 1996, Wheathills Resources Inc. completed a program of prospecting, rock sampling and trenching on the area.