The Shawn occurrence is located just west of Captain Lake, about 146 kilometres north of the community of Dease Lake and 28 kilometres south of the British Columbia-Yukon border.

At the Shawn (Captain Lake) showing, Middle-Upper Devonian McDame Group platformal carbonates host coarse grained, white, stratiform barite interbedded with dolomitic siltstones 100 metres above the McDame-Lower Devonian Tapioca sandstone contact. Barite also occurs as crosscutting veins and breccia clasts or replacement zones up to 1 metre across in both the McDame Group and Tapioca sandstone. Graded sedimentary breccias, with barite, McDame and Tapioca clasts, occur stratigraphically above the bedded barite. This style of mineralization suggests a continuum between crosscutting veins and exhalative barite. The overlying sedimentary deposits may have resulted from coeval mineralization and fault movement locally exposing Tapioca sandstone (Fieldwork 1987).

This property was originally recognized as a copper prospect (Geological Survey of Canada Map 1110A). Minor amounts of chalcopyrite occur in small hematitic zones with malachite. In 1981, Dekalb Mining Corporation staked the Shawn claim and completed a trenching, mapping and sampling program. One old trench was extended and three new trenches were cut into the side of the hill crosscutting the barite zones. A total of 30 chip samples were taken over all the zones where barite occurred in the trenches. The trenching program exposed numerous bands of barite-bearing rock; the main barite zone is over 35 metres wide and consists of six barite-rich bands that individually are up to 5 metres wide. This zone was traced on the surface for up to 120 metres in length. Barite boulders were found up to one kilometre northeast of the trenches. One high grade grab sample of barite assayed 95.7 per cent BaSO4 with a specific gravity of 4.41 (Assessment Report 10334).