The Iron Cap showing is about 1.3 kilometres southeast of the north end of Long Lake and about 1.1 kilometres east of the east shore of the lake, 22 kilometres north of Stewart. The mineralized horizon is exposed along the south side of Joan Creek.

The area is underlain predominantly by Hazelton Group volcanics that lie in the crumpled core region of the north-northwest trending Spider anticline. In the core of the fold, Lower Jurassic Unuk River Formation rocks are successively overlain by the Lower Jurassic Betty Creek and overlying Mount Dilworth formations. The mainly volcanic rocks are overlain by the predominantly sedimentary rocks of the Middle-Upper Jurassic Salmon River Formation. Northwest trending dikes of the Portland Canal dike swarm intrude all rock types. Several north-northwest trending faults are conspicuous in the area (Open File 1987-22).

Mineralization is hosted in a south-southeast striking, gently east dipping dacitic ash tuff of the Lower to Middle Jurassic Mount Dilworth Formation. The iron-stained outcrop can be traced for about 1000 metres. The uppermost one metre of the flow is heavily impregnated with fine-grained pyrite that appears to form vesicle fillings. Minor chalcopyrite, galena and sphalerite are also reported. Pale blue chalcedony forms minute blebs and veinlets.

Low but consistent silver, lead and zinc values are reported from two opencuts on the zone. In 1956, a channel sample collected from the upper cut assayed 6.9 grams per tonne silver and trace gold across 2.4 metres (Property File - Plumb, 1956).

Work History

The complete history of the showing is unknown. The extensive gossan probably attracted many prospectors over the years. In 1956, the showing was covered by the M.J. claims, owned by the M.J. Mining Syndicate. The owners emplaced at least two opencuts. In 1956, Plumb examined the showing for Dorreen Mines Limited.

In 2017, Richard Billingsley completed an airborne magnetic survey on the area. In 2019, AUX Resources Corp. completed a program of prospecting, geological mapping and rock sampling on the area as the Independence and Slippery Ian properties.