The Rubyrock Creek occurrence is located on a gentle west-trending ridge, south of the west end of Starret Lake and approximately 7.5 kilometres north of the northwest end of Cunningham Lake.

Regionally, the area is underlain by serpentinite ultramafic rocks and ultramafics of the Trembleur ultramafic unit and gabbroic to dioritic intrusive rocks and greenschist metamorphic rocks of the Rubyrock Igneous Complex, both of the Lower Permian to Upper Triassic Cache Creek Complex. The Cache Creek Complex rocks have been intruded by small bodies of Eocene granodioritic rocks and are overlain by basaltic volcanic rocks of the Eocene to Oligocene Endako Formation (Nechako Plateau Group).

Mapping within the Trembleur ultramafic unit along the crest of the ridge northeast of Rubyrock Creek resulted in the discovery of several small outcrops of crowded biotite-feldspar porphyritic granodiorite with up to 15 per cent disseminated and fracture-controlled pyrite. These outcrops occur in a small saddle and define an area of sulphide mineralization that is at least 300 metres long and 200 metres wide. The extent of mineralization is constrained to the west by the occurrence of unmineralized serpentinite but is open in all other directions.

The discovery is considered significant because the style of sulphide mineralization and the nature of the porphyritic hostrocks suggest the presence of a probably Eocene porphyry copper–style hydrothermal system. Although no significant copper mineralization was located within the zone of disseminated and fracture-controlled pyrite, follow-up work may locate a copper-rich zone associated with the porphyritic intrusions.

A single sample collected from this locality contained 0.018 per cent copper (Geological Fieldwork 1998, page 34).

Work History

In 1988, Lacana Mining Corp. completed a program of prospecting and geochemical (rock, silt, and soil) sampling on the W. Boyd 1 claim, located southwest of Rubyrock Lake and approximately 8.5 kilometres southeast of the Rubyrock Creek occurrence. A chip sample (11302) over 1.5 metres from a 0.3-metre wide silicified zone in a sheared to brecciated, kaolinite-altered intrusive assayed 0.054 per cent copper (Assessment Report 18120).

In 1990, U.G. Mowat prospected and sampled the W. Boyd claim.

In 2007, Amarc Resources Ltd. held the area as part of the Megmine property. A soil sampling program was completed on the Megamine 5 and 6 claims to the west of the Rubyrock Creek occurrence and identified a copper-in-soil anomaly on the west side of Megamine 5 claim.