The Princeton porphyry copper deposits are part of a northerly trending Mesozoic tectono-stratigraphic Quesnellia terrane which is composed of a volcanic arc with overlying sedimentary sequences, all of which were built on top of a deformed, oceanic sedimentary-volcanic complex (Harper Ranch and Okanogan sub-terranes). Quesnellia was formed off-shore to the southwest of continental North America and accreted, with other terranes, onto North America in late Mesozoic times (Monger et al., 1992). The Late Triassic Nicola Group, a predominately subaqueous island-arc assemblage composed of volcanic and lesser sedimentary rocks forms the bulk of the Quesnellia terrane. The Nicola Group rocks have been intruded by early Jurassic alkalic, calc-alkalic and zoned mafic (Alaska-type) plutons and batholiths (Preto, 1972; 1979).
The Castle property is mainly underlain by basaltic and andesitic flows of the Upper Triassic Nicola Group. The Nicola volcanic rocks strike in a northwest direction and are in contact with a Middle Jurassic-age granodiorite Osprey Lake Batholith in the northeast portion of the property. Rocks of the Nicola Group exposed on the property consist mainly of plagioclase and or olivine porphyritic basaltic flows and altered andesitic flows. Multi-directional shearing or fracturing is evident in outcrop and epidote and chlorite are abundant as fracture coatings. Outcrop on the property is restricted to high ridges exposed to the north of Christian Creek.
The deposit target for the Castle property is a copper-gold porphyry deposit similar to those found at Copper Mountain some 25 km south of the Property.
The Copper Mountain deposits are classified as alkalic porphyry copper deposits with associated gold and silver credits. Porphyry copper deposits come in two major types with the Calc-Alkalic type being significantly more abundant than the Alkalic type. Porphyry molybdenum-copper deposits of the calc-alkalic variety provide more than 50% of the world's copper from over 100 producing mines. Alkalic porphyry deposits (Barr, et.al., 1976) are quite distinct from the more common calc-alkalic genre and represent an important subclass of deposits. The alkalic deposits of British Columbia are spatially and genetically associated with the Upper Triassic Nicola-Takla-Stuhini volcanic assemblages and co-magmatic plutons.
Mineralization is found on the property in a series of trenches excavated in the mid 1980's by Count Fleet Exploration and re-established by Blue River. The trenches occur on a south facing ridge above Christian Creek. The exposed mineralization consists primarily of malachite, chalcopyrite, pyrite and magnetite, with minor bornite and possibly chalcocite. The copper minerals are confined largely to a 150m wide zone trending west-northwest for 500m.