The Mat North occurrence area is underlain by rock of the Upper Triassic Cake Hill pluton, part of the Jurassic-Triassic Hotailuh batholith. The pluton consists mainly of hornblende quartz monzonite, granodiorite and rare hornblende diorite. The showing is found on the east face of an alpine ridge

The Mat North showing is hosted by the Late Triassic Cake Hill pluton and comprises decimetre-size pods containing about 5 per cent disseminated sulphides (pyrite, possible bornite; chrysocolla and malachite staining common). One assay sample returned greater than 1 per cent copper, 9.1 grams per tonne silver slightly elevated gold and bismuth (11BVA25-172 in Fieldwork 2011, Table 2). Abundant coarse-grained euhedral biotite immediately surrounds the mineralized pods, but is absent further away in the plutonic rocks.