The Pat Lake showings comprise two antimony-bearing silica replacement zones in Upper Triassic Nicola Group metasediments. The replacement zones are surrounded by weak carbonate alteration and appear to be related to high-level quartz eye porphyry intrusions. The emplacement of the intrusive rocks and the mineralized replacement zones associated with them are controlled by late northeast and east striking faults cutting the Nicola rocks. The original showing, Pat Lake, is 50 metres from the south shore of Pat Lake and has been exposed by shallow blasting over an area of 4 square metres by earlier workers. This showing lies within 150 metres of a quartz-eye felsic intrusion. The second showing, discovered in 1989, lies 500 metres west.
The Nicola metasediments generally strike 010 to 015 degrees and dip steeply southeast. The volcaniclastic metasediments are comprised predominantly of basaltic material, although andesitic and trachyandesitic clasts are also common. The metasediments range from siltstones to medium and coarse-grained sandstones to grits and pebble to cobble conglomerates and are locally folded and warped.
The most noticeable alteration is limonite staining derived from the weathering of ankerite which occurs as a replacement mineral within the metasediments. Late ankerite, dolomite and chalcedony veinlets cut the metasediments locally. The style of mineralization at both showings are similar, with blebs and smears of stibnite occurring in highly silicified, brecciated shear zones in andesitic volcaniclastic sandstone. The concentration of stibnite at the original Pat Lake showing (1-5 per cent) is greater than that at the 1989 discovery showing (1-2 per cent).
The showings have been the target of sporadic exploration dating back to 1982 when they were covered by the Sprout 3 claim owned by Newmont Exploration of Canada Ltd. The original stibnite showing, Pat Lake, was 'rediscovered' by Newmont in 1982-83 when they were conducting reconnaissance geological mapping and widely spaced geochemical soil surveys. In 1988, the London claim was staked over the showing and a detailed soil survey (58 samples) was conducted in 1989 by M. Morrison who discovered a second stibnite showing, located 500 metres west of the Pat Lake showing. In 1990, additional claims were staked to adjoin the London claim and in 1991-92 ground magnetometer surveys (9.6 kilometres) were run. In 1995, the Stibnite claims were staked over the showings and in 1996 geological mapping was undertaken by M. Morrison. In 1999, M. Morrison conducted an experimental biogeochemical survey and collected 15 samples of organic growth for testing. In 2001, M. Morrison completed geological mapping and collected 6 rock samples. See also Newmont (092INE070).