The area of the Top occurrence is underlain by Lower Jurassic felsic rocks of the Hazelton Group.

Prospecting and mapping in the Top area in 2005 on behalf of Rimfire Minerals Corp and Northgate Minerals Corp identified two areas of disseminated galena mineralization. One is just below the peak on the west side of the ridge above the southern Wedge zone (104G 144) and is thought to occur within dacite tuff beds that are apparently dipping roughly parallel to the slope, possibly exaggerating the extent of mineralization. Another zone occurs in local float in the main saddle near the south end of the Wedge Zone, close to the Gossan Creek porphyry. Here galena is disseminated in carbonate veinlets and fractures in dacite crystal tuff to dacitic wacke. Locally, tetrahedrite is suspected to be present due to malachite and azurite staining. Overall, mineralization is scattered in an area about 600 metres north-south by 200 metres east-west.

A 5 metre grab sample assayed 41.1 grams per tonne silver, 0.13 per cent copper, 3.54 per cent lead and 0.43 per cent zinc (Assessment Report 28107, Sample B392288).

Refer to RDN (104G 144) for details of a common work history.