Strata underlying the Baltic, from oldest to youngest, include: conglomerates and coarse clastic sediments of the Upper Proterozoic Toby Formation (Windermere Supergroup); slates, quartzites, grits and conglomerates of the Upper Proterozoic Horsethief Creek Group; dolomites of the Cambrian Jubilee Formation; argillite and dolomite of the Cambrian to Ordovician McKay Group; dolomite, shale, sandstone and quartzite of the Ordovician to Silurian Beaverfoot Formation; and argillite, argillaceous limestone and quartzite of the Devonian Mount Forster Formation.

Two lead showings were mapped on the south side of the Forster Creek valley in an area of extensive overburden. The exposed showings, BZS-1 AND BZS-2, comprise disseminated sphalerite and galena along fractures in limestone and dolomites of the Beaverfoot Formation. Minor replacement textures in the carbonate are exhibited adjacent to the fracture mineralization. The BZS-1 showing is the better of the two and has interbedded shale and carbonate lithologies.

In 1990, Cominco did some mapping and investigation on the Baltic 10 property, owned by A. Louie. Prior to 1990, Cominco had investigated showings on the Baltic claims on the north side of Forster Creek. See Baltic (082KNE064) for details.