Minus one-valent sulphur is required for the precipitation of pyrite/marcasite. Various mechanisms to produce S-1 for the putative depositional conditions of Mississippi Valley-type deposits are all problematic. Nevertheless, the problem exists and constrains any proposed genetic hypothesis.-G.J.N.
Additional publication details
The valence of sulfur in disulfides-an overlooked clue to the genesis of Mississippi Valley-type lead-zinc deposits.