The Barndoor occurrence is located on a small ridge south of Yohetta Ccreek and approximately 5 kilometres north of R.C.A.F. Peak.
The area is underlain by calc-alkaline volcanics and sedimentary rocks of the Lower Cretaceous Tchaikazan River succession and undivided volcanic rocks of the Upper Cretaceous Powell Creek Formation. Quartz dioritic intrusive rocks of the Late Cretaceous Anvil Mountain suite outcrop to the north.
Locally, malachite and silver minerals occur in narrow quartz-carbonate and/or quartz-epidote fractures in altered basalt flows and andesites. A barren, 2 metre wide, quartz vein is also present.
In 1982, a sample (AS 1203) assayed 9.4 per cent copper and 82.1 grams per tonne silver, while other samples (AS 1216) yielded up to 0.62 gram per tonne gold (Assessment Report 10744). The following year samples yielded up to 1.42 per cent copper (Assessment Report 12105).
The area has been historically explored in conjunction with the nearby Charlie (MINFILE 092O 043) occurrence. During 1981 through 1983, Suncor Resources completed programs of rock, silt and soil sampling, geological mapping and ground geophysical surveys on the area as the Cougar claims. In 1998, Pellaire Gold Mines completed a program of rock, silt and soil sampling on the area. In 1999, NWC Explorations completed a program of geochemical sampling, geological mapping, a 188 line-kilometre airborne geophysical survey and three diamond drill holes, totalling 660.3 metres, on the area as the Northwest Copper property. In 2005, Galore Resources completed a program of soil sampling, a 61.8 line-kilometre ground geophysical survey and a 188 line-kilometre airborne geophysical survey on the area. In 2008, Valor Resources completed a program of geochemical sampling and geological mapping on the area. The following year, program of rock, silt and soil sampling was completed. During 2009 through 2014, Zelon Chemicals completed programs of rock, soil and biogeochemical sampling, minor trenching and a ground geophysical survey on the area.