This occurrence is located on the southwest flank of Crowfoot Mountain, 16 kilometres north of Maona Bay on Shuswap Lake.

Two limestone horizons of the Tshinikan Member of the Eagle Bay Formation outcrop in the headwaters of Onyx (Manson) Creek. The two horizons are separated by 137 metres of interbedded phyllite and quartzite. The entire sequence is intruded by a few lamprophyric to dioritic dykes and sills. The beds generally strike 090 degrees and dip 45 degrees north. Archeocyathids found in a correlative carbonate unit near Vavenby to the north indicate a Lower Cambrian age (Geological Fieldwork 1985, page 92).

The upper horizon is comprised of approximately 46 metres of white to greyish white, white weathering, medium grained (1 to 2 millimetre) recrystallized dolomitic limestone that is cut by a network of opaque, white quartz veins near contacts with the enclosing host rocks. Some patches and seams of buff coloured, argillaceous and siliceous rock occur within this horizon. Minor graphite is also present. Near the base of the unit the limestone is intruded by some porphyritic, lamprophyric dykes at least 1.5 metres wide. This limestone horizon outcrops over a 300 by 90 metre area.

The lower 18 metre thick horizon contains fine grained, white weathering limestone with some pyrite. A variable magnesium and silica content is displayed up section and along strike.

The deposit was staked by Omar Paquette in 1973. Development work is limited to some trenching and diamond drilling.