At the Illecillewaet showing, a pit 1 by 5 metres long exposes a shear zone in Lower Cambrian and younger Lardeau Group slates and limestone (dolomite?). Talc is found in the shear, and in outcrops extending for 600 metres. The talc is greenish grey to white, translucent and mixed with pale green actinolite (fibrous actinolite is referred to as amphibole asbestos in old reports).

An occurrence of steatite in dolomite is also reported about 10 kilometres west of the Illecillewaet showing, on Ross Peak.