The B occurrence is located approximately 80 kilometres east of the community of Dease Lake.

The area is underlain by northwest trending Mississippian to Triassic Cache Creek Complex rocks including metavolcanics, metasediments and tectonically emplaced ultramafic rocks of upper Mississippian to Permian age. The Cache Creek ultramafic rocks consist of peridotite, dunite and pyroxenite which are generally serpentinized.

These rocks also contain pods of nephrite jade, two of which are plotted on Geological Survey of Canada Open File map 2779 in the immediate vicinity of the B13 asbestos showing. The characteristics of these pods are not documented.

In 1966, small amounts of medium length chrysotile asbestos (5 to 8 millimetres) were reported to occur on the B13 claim (Assessment Report 825). Although apparently initially independent of Cassiar Asbestos Corporation's Letain Asbestos deposit (104I 006) located 1.7 kilometres northwest, by 1966 the claims were part of those holdings.