The Dan occurrence area is underlain by Helikian Fort Steele Formation (Purcell Supergroup) metasedimentary rocks consisting of quartzites, siltstones and argillites. Regionally, the rocks are intruded by Cretaceous felsic intrusives of syenite to granodiorite composition.

The property covers a series of east striking, steeply dipping felsic dykes which range in composition from syenite to quartz monzonite and possibly granodiorite. Mafic diorites or gabbros are also present but these may be part of the Proterozoic Moyie Intrusions. Some of the felsic dykes contain disseminated sulphides, mainly pyrite but with minor galena and chalcopyrite; siderite and pyromorphite are also evident. Some of the dykes may also have associated marginal brecciation and quartz veining. A rock sample of a 12 centimetre wide quartz vein on the footwall contact of a syenite dyke assayed 1.08 per cent lead, 0.13 per cent copper and 9.5 grams per tonne silver (Assessment Report 20103).