The Lucky Jack area is underlain by sandstone, siltstone and conglomerate of the Middle Jurassic to Lower Cretaceous Bowser Lake Group. These have been intruded by stocks of the Upper Cretaceous Bulkley Plutonic Suite. They range compositionally from diorite-quartz diorite to granodiorite and tonalite, and texturally they include both equigranular and porphyritic varieties. A contact metamorphic hornfels has developed for 300 metres or more around the intrusive. The sedimentary rocks are highly fractured and, locally, hydrothermally altered.

The 11.5 metre long trenched Lucky Jack comprises mainly dark argillite that is locally bleached, as well as minor amounts of possible rhyolite-dacitic rocks. The argillites are mostly massive, but in places there is vague layering (possibly bedding) that strikes northeast and dips 40 to 48 degrees southeast.

The argillites contain several sulphide zones that could include both bedding-parallel and cross-cutting, fracture-controlled veins. The two thickest, sub-parallel veins lie 5 metres apart. The most northerly of these varies between 3 and 12 centimetres thick, and it changes in trend along its exposed 2.5 metre strike length. The other zone to the south varies from 1 to 4 centimetres in width. Overall, they both trend north-northeast (azimuth 030 degrees) and dip 30 to 40 degrees southeast; this is a similar dip and trend to the Marc occurrence further south. At the extreme northern end of the outcrop there may also be a third, but thinner (1 centimetre) vein. This is highly altered with white and yellow oxide alteration. It has a similar strike as the two others and dips 48 degrees southeast. The two thicker and less oxidized zones contain coarse crystalline pyrite, black sphalerite, stibnite and abundant yellow lead oxides. The outcrop is also cut by a weakly mineralized fault or fracture, 1 centimetre thick, which strikes 150 degrees and dips 55 degrees southwest.

A sample taken in 2008 assayed 937 grams per tonne silver, 2.78 grams per tonne gold, 0.13 per cent copper, greater than 4 per cent lead, 0.43 per cent zinc, 3.1 per cent arsenic and 3.6 per cent antimony (Assessment Report 30787).

The Lucky Jack is included as a sediment-hosted vein with gold and silver values.

Refer to Max (093M 027) for further geological details and a common work history.