The Rio Creek showing is located about 5 kilometres south of the British Columbia - Yukon border, near the Primrose River where granitic rock displays moderate to very strong fracturing, weak hydrothermal alteration and strong pyritization. A prominent colour anomaly covers the area that contains the Silt (104M 054), Pit Creek (104M 055) and Rio Creek occurrences.

The chief lithology underlying the property is Paleogene (Paleocene to Oligocene) alaskite to leucocratic quartz monzonite. This unit is medium to coarse-grained, equigranular and deep brown to orange on weathered surfaces, due to the oxidation of very fine-grained disseminated pyrite. In contact with the granite on the northeast of the property is weakly fractured, grey, unaltered coarse-grained feldspar porphyry granodiorite. Middle Devonian paragneiss occurs to the southeast and Mid-Cretaceous and Late-Cretaceous granites occur farther west and south. A strong fracture system was reported to occur over a 1 by 5.5 kilometre area over the 1978 Silt property.

Traces of fracture-controlled, disseminated and vein molybdenite are also widespread over the property. The outer limits of molybdenite mineralization on the Silt property were not met in the area examined in 1978. All showings observed were within rusty granite, but many boulders of unaltered, non-ferruginous molybdenite-bearing intrusive rock were seen in creek bottoms. Outcrops along Rio Creek contain fractures lined with fine-grained quartz and light-green muscovite, sporadically mineralized with sphalerite, galena, chalcopyrite, cassiterite, and fluorite (Assessment Report 7336). One 3-metre zone contains subparallel bands of sphalerite and galena, 2 to 10 centimetres wide.

WORK HISTORY

Kennco Explorations, (Western) Limited reportedly carried out a regional geochemical survey over the area in 1965 and examined some of the showings. Canadian Super Exploration Limited held the ground in 1970 as the Sue group and some work was apparently done by Archer Cathro & Associates Ltd. The area was staked by J. Hansen of Atlin , B.C., 1978 and was reported to be held by Pinto Resources Ltd. of Vancouver (Assessment Report 7336). The claim area was prospected and mapped geologically in early August and a number of geochemical samples were collected, including bulk stream sediment samples for heavy mineral studies. During 1978, Pinto documented mineralization on Silt prospect (Main showing), Pit Creek (B showing) and Rio Creek (Fracture zone). A high of 9580 parts per million (0.96 per cent) molybdenum and 60.3 grams per tonne silver were derived from a heavy mineral sample using a 20-35 mesh sieve (Assessment Report 7336).

In 1980, Orex Mines Ltd., a private company owned by M. and L. Jorgensen of Vancouver, was incorporated in order to acquire the property. Helgena Mines Ltd. optioned the claim from Orex in December 1980.

See the Silt and Pit Creek MINFILE occurrences for more information on the molydenum that occur on the Silt property.