Precambrian-Paleozoic(?) Monashee Complex (Group) rocks are exposed in the Thor-Odin gneiss dome, a part of a large domal complex in the central, eastern part of the Shuswap Metamorphic Complex. The dome is characterized by a structural-stratigraphic succession divided into four lithologically distinct zones. These are: the Core Zone, comprising migmatitic and granitic gneisses in the central part of the gneiss dome; the Mantling Zone, well-differentiated metasedimentary rocks ranging from quartzite and marble through calcsilicate gneiss to pelitic schist; the Fringe Zone, in part overlapping, and in part surrounding the Mantling Zone and characterized by large amounts of granitic and pegmatitic rocks; and the Supracrustal Zone that lies outside the gneiss complex, and forms a cover to the gneisses.

Pure, coarsely crystalline quartzite is common among strata of the Monashee Complex. These rocks are free from iron-bearing minerals, appear translucent white in hand specimen, and are so homogeneous as to be almost devoid of internal bedding or lamination. Such quartzite may be a potential source of silica for industrial uses where a high degree of purity is demanded. Relatively pure quartzites in the Mantling Zone of the Thor-Odin dome occur on the southerly slopes of Mount Odin.