The O-1 occurrence is located near the southeast corner of the O-1 claim (ca. 1987), east of Spruce Mountain and south of Surprise Lake, about 19 kilometres east of the community of Atlin (Assessment Report 16312).
The showing area is underlain by Cache Creek Complex rocks consisting primarily of mafic volcanics of the upper Mississippian to Permian Nakina Formation and cherts and argillite of the Mississippian to Triassic Kedahda Formation. These rocks are intruded by upper Mississippian to Permian Cache Creek Complex ultramafic rocks. The ultramafics are characterized by serpentinization, carbonatization and the development of talc locally.
Intensely altered ultramafics (listwanite?) on the O-1 claims are reported to contain 1 to 5 per cent pyrite, minor chalcopyrite and sphalerite. Significant amounts of quartz veining are also present. Samples taken did not contain significant amounts of gold (Assessment Report 16312).
In 1987, Ezekiel Explorations Ltd. carried out a program consisting of trenching, rock chip sampling and a proton magnetometer survey. A total of seven trenches and 105 line kilometres of magnetometer survey were completed.