At the Col showing, sphalerite, smithsonite, galena and barite are hosted in an east trending fault zone within Middle-Upper Cambrian Jubilee Formation dolomites.

Mineralization is associated with podiform barite, barite-healed fractures and/or tectonic breccia or crackle development. The zinc-lead mineralization is normally concentrated at the margins of the barite pods but is occasionally disseminated within them. There are traces of pyrite but there is no silicification or evidence of karst development of the sedimentary stratigraphy.