The Easy M occurrence is located on the access road to the Duncan Dam, 500 metres west of the dam, in the Slocan Mining Division.

Regionally, the area lies within the Kootenay Arc near the margins of the Ancestral North American Terrane. The Kootenay Arc is a curving belt of highly deformed metasedimentary and metavolcanic rocks which includes the Upper Proterozoic Horsethief Creek Group, the Eocambrian Hamill Group, the Lower Cambrian Badshot Formation, and the lower Paleozoic Lardeau Group. The volcano-sedimentary sequence is intruded by numerous Ordovician, Devonian and Mississippian granitoid plutons. The rocks have undergone regional metamorphism to middle or upper greenschist facies (Paper 1993-1).

Excavation associated with the construction of the Duncan Dam exposed stringers of sphalerite with minor galena in quartz veinlets. The veinlets are hosted in grey-blue crystalline dolomitic marble of the Lower Cambrian Badshot Formation near its lower contact with a micaceous schist of the Marsh Adams Formation of the Hamill Group. A 10 centimetre wide veinlet of massive sphalerite strikes northwest and dips 70 degrees to the east.