The Lardeau River placer occurrence is situated on the Lardeau River between Poplar and Cascade creeks in the Slocan Mining Division.

Regionally, the area lies within the Selkirk Mountains of southeastern British Columbia. The occurrence is within the Kootenay Arc, a curving belt of highly deformed metasedimentary and metavolcanic rocks which includes the Upper Proterozoic Horsethief Creek Group, the Upper Proterozoic to Lower Cambrian Hamill Group, the Lower Cambrian Badshot Formation, and the Paleozoic Lardeau and Milford groups. The volcano-sedimentary sequence is intruded by numerous Paleozoic to Mesozoic granitoid plutons.

The Lardeau River area of the Selkirk Mountains is mainly underlain by massive pillow lavas, volcanic breccia and green phyllitic rocks of the Index Formation and by grey-green mica schist of the Broadview Formation. Grey phyllitic rocks and marble of the Milford Group are exposed near the edges of the Mesozoic Mobbs Creek, Rapid Creek and Poplar Creek stocks. All rocks have undergone regional metamorphism to middle or upper greenschist facies. Rocks of the Milford Group have also been affected by thermal metamorphism (Geological Survey of Canada Bulletin 193).

The earliest records of placer mining in the Lardeau River dates back to the late 1890s when most of the production was achieved. Placer mining activities continued sporadically in the area between Poplar and Cascade creeks until the mid-1940s but little production was achieved. Gold was being extracted from gravel accumulated in sand bars but the work was hampered because of the presence of abundant large boulders. Total production from the river amounts to 8553 grams of gold with an average fineness of 808 (Bulletin 28). Records also indicate that some gold was extracted from the gravels of Cascade and Poplar creeks although no amounts of production are available (GSC Bulletin 193).