The Woss Lake No.1 occurrence is reported to be located 0.4 kilometres east of the quarry at Woss Lake 4 (MINFILE 092L 064) in Assessment Report 4568. Assessment Report 663 reports it as showing No. 3.

The region of the Woss Lake occurrences is underlain by a thick sequence of north trending, gently west dipping tholeiitic basalts of the Upper Triassic Vancouver Group, Karmutsen Formation which is in fault contact with andesitic to dacitic basalts and minor sediments of the Lower Jurassic Bonanza Group. Granodiorite of the Late Jurassic Island Plutonic Suite has intruded the older rocks. The presence of a 60 to 90 metre limestone unit interbedded with basalts suggests that the rocks at the occurrence are part of the Bonanza Group.

At the occurrence, amygdaloidal, porphyritic and fine-grained basalts are intruded by a complex of reddish porphyritic monzonite dykes related to a granodiorite batholith one kilometre to the north- east. The contact between the basalts and the granodiorite dips southwest at 26 degrees.

Mineralization consists of massive magnetite with minor disseminated pyrite, replacing limestone at an intrusive contact. Dip needle readings suggest the zone of mineralization extends over 15 by 15 metres (Assessment Report 663).

In 1965, Empire Development completed a program of geological mapping and a dip needle survey on the are as the Woss Lake 1-6 claims. In 1972 and 1973, programs of geological mapping and ground electromagnetic and magnetic surveys were completed. In 1985, Archer Minerals completed a program of rock and soil sampling on the area as the Riviera claim.