The CLIFF prospect is located on the OUTBACK property in the Granby River valley, approximately 25.5 kilometres west-southwest of the village of Edgewood.
The general area is underlain by gneiss of the Proterozoic Monashee Complex. Within the Granby River valley there is a north trending, easterly dipping normal fault. Along this fault andesite of the Eocene Marron Formation (Penticton Group) is preserved. Co-magmatic with the Marron Formation are Eocene Coryell Intrusions which form small isolated intrusions throughout the area. The Coryell Intrusions are largely syenitic in composition, although a quartz-feldspar porphyry found on the prospect may be a calc-alkaline variation. A quartz monzonite intrusion, which hosts mineralization at the CLIFF prospect, may be an unnamed Middle Jurassic intrusion.
Mineralization in the CLIFF prospect consists of a stockwork of hairline to centimetre sized, milky-white, drusy, chalcedonic quartz veining which occurs over an area measuring approximately 500 metres by 150 metres. Both disseminated and thin stringers of pyrite are found in the veins. Gold-silver mineralization, which is associated with pyrite, is especially pronounced near the contact between a quartz-feldspar porphyry and the host quartz monzonite. Magnetite is also noted. A prominent north-northwest trending fault cuts through the mineralized area and is terminated by the quartz-feldspar porphyry. A cataclasite unit is described as varying from densely foliated to weakly mylonitic. Propylitic (epidote, chlorite, pyrite and calcite) alteration is pervasive in the quartz monzonite. Weak to intermediate argillic (kaolinite) alteration is common within 25 metres of the contact between the quartz-feldspar-porphyry and the quartz monzonite. Fine-grained sericite is noted in vein envelopes.
The OUTBACK property, which contains the CLIFF prospect, was staked in 1988-89 by the Canadian Nickel Company Limited (INCO). INCO carried out several field programs of stream sediment sampling, follow-up prospecting, soil sampling and geological mapping in 1989. The gold potential of this area was identified through the use of heavy mineral stream sediment techniques.
In 1990, INCO carried out detailed soil sampling, prospecting, geological mapping and extensive rock sampling on a number of gold- silver occurrences in this area. These include the nearby BETH (082ENE068), LEAH (082ENE069), JANE (082ENE070), and TARA (082ENE071) occurrences. On the CLIFF prospect, INCO carried out detailed grid soil sampling, prospecting, mapping at 1:5000 scale and extensive rock sampling. Chip samples assayed up to 14.5 grams per tonne gold over 2.6 metres, 1.2 grams per tonne gold over 5.5 metres and 6.42 grams per tonne gold over 4 metres, including 1 metre of 18.1 grams per tonne gold (Assessment Report 21916).
In 1991, a 6-hole, 807.1-metre diamond-drill program was carried out on the CLIFF prospect by INCO. All holes were drilled from the same set-up. A number of intersections assayed greater than 0.5 gram per tonne gold, including a 12.2-metre intersection in drillhole BH 87004 which assayed 0.83 gram per tonne gold, and contained a 0.45-metre intersection of 5.2 grams per tonne gold and 61.0 grams per tonne silver (Assessment Report 21916). High-grade intersections contained fine-grained pyrite with electrum and acanthite replacements. The drill program resulted in a re-interpretation of the prospect as a porphyry-gold deposit type, from the original epithermal interpretation.
