The McArthur lead-zinc-silver deposit is of the stratiform type. It consists of a mineralised bituminous shale sequence containing some tuffites, numerous graded beds and isolated slump breccia horizons._x000D_
The principal sulfides; pyrite, sphalerite and galena, are essentially restricted to the shales and the genetically unrelated turbidites contain only minor mineralisation._x000D_
The geochemistry of the deposit has been investigated with respect to the stratigraphic column and mineralogy of the sediments._x000D_
A sedimentary origin is advocated for the deposit. Volcanism, thermal spring activity and high salinities, perhaps related to the Emu Fault, are considered as contributing factors to ore genesis._x000D_
The metallurgy of this deposit is discussed in relation to its geologic history.