The Rafferty prospect is located on the north side of the North Thompson River at Adolf Creek, 48 kilometres northwest of the community of Blue River. The deposit was trenched and sampled by Pacific Mica Ltd. in 1984 and 1985.
The area is underlain by quartz mica schist, quartzite and phyllite of the Upper Proterozoic lower Kaza Group. A northwest trending thrust fault is interpreted to separate the Kaza Group from overturned strata of the Hadrynian Horsethief Creek Group to the northeast. The main metamorphic event has been dated to have occurred at 135 +/- 4 Ma (Geological Survey of Canada Paper 90-1E, pp. 71-80). Refer to the Canoe South Mica showing (083D 017) for a detailed description of the regional deformation and metamorphism.
The deposit is comprised of two distinct zones of muscovite rich schist. A zone of quartz-muscovite-biotite schist, 65 metres wide, trends 115 degrees for at least 250 metres, possibly up to 1350 metres, and dips steeply southwest. Minor garnet and locally intense iron staining due to pyrrhotite are present. The zone grades northeastward into interbedded quartz-hornblende-biotite-garnet schist and quartzite. The zone is in sharp contact to the southwest with quartzite and micaceous quartzite. A second less well defined zone (the M-10 zone) occurs southwest of the previous zone, where large blocks of quartz mica schist are exposed on the steep north bank of the North Thompson River. The blocks are likely slumped material, only slightly removed from bedrock.
Schist samples from the main zone are reported to contain 44.47 per cent muscovite, of which 15 per cent was contaminated with graphite (Assessment Report 13844). Muscovite from the M-10 zone was found to be free of graphite. Grinding and beneficiation tests, performed at the University of Toronto, indicate that a concentrate, containing at least 95 per cent muscovite, can be produced. Good liberation and separation occur in the 0.15 to 0.6 millimetre size range (Assessment Report 12679).