The Mal occurrence is underlain by coarse-grained quartz monzonite of the Early to Middle Jurassic Island Plutonic Suite (formerly the Island Intrusions). The monzonite contains inclusions of saussuritized quartz diorite of the Mesozoic and/or Paleozoic Westcoast Complex and volcanic rocks. These rocks are cut by several southeast trending, steeply dipping, slightly porphyritic andesite dykes.

The mineralization occurs in a fault zone about 7.6 metres wide striking 130 degrees and dipping 75 degrees to the northeast. The fault cuts the monzonite, quartz diorite and the andesite dykes. A few light coloured granitic stringers a few centimetres in width have been intruded along the fault.

Chalcopyrite, sphalerite and pyrite occur in the fault in bands or lenses up to 0.6 metres wide. The gangue consists of quartz, chlorite, clinozoisite, actinolite, hypersthene and a black opaque iron-silicate mineral thought to be thuringite. The sphalerite is a dark variety and veins the thuringite.

Six shallow diamond-drill holes over a 90 metre length of outcrop averaged 2.17 per cent copper, 1.94 per cent zinc and 72.69 grams per tonne silver (National Mineral Inventory 092C10 Cu1).