Résumé
The hydrothermal native element-arsenide mineralization (five-element) type comprises native Ag and/or native Bi as well as Ni-, Co-, and Fe-arsenides and-sulfarsenides. Due to the current surge in Co-demand, this mineralization type has regained recent economic interest. Thus, it is of interest to further understand the paragenetic and possible spatial relation of Co-bearing minerals and the formation mechanism/process of this mineralization type. This is achieved through an extensive literature review in combination with newly calculated stability relations. The mineralization is host rock independent, but spatially linked to sources of reducing agents (as this is the cause of precipitation). This reduction process results in a thermodynamically controlled characteristic Ni- Co- Fe-diarsenides sequence, as well as a transition from native elements to mono-to di-arsenides. The temporal Ni Co Fe trend has also been described to occur on a special scale, and since it is ubiquitous, it may be used as a tool in constraining Co rich sections of a deposit. The formation of this mineralization is, however, not only thermodynamically, but also kinetically controlled, as is evident by the abundant dendritic textures. Kinetics favor a sulfate-sulfide disequilibrium which enables an aqueous sulfide poor system that allows for arsenide formation.