Gold in Metamorphic rocks: Facts and Fancy

Abstract

The characterization of shear zone related ores (SZRO) is still a matter of debate. In an attempt to attenuate the existing controversial points of view some classifications of the SZRO are here proposed, taking into account both their mineralogy and geochemistry (protore nature, ore minerals assemblages etc.) and their size. The small scale SZRO seem to depend on the existence of a protore, as a source of metals, whereas the large scale SZRO may have an epigenetic overprint and the source of metals can be multiple, juvenile included. Finally, a fractal-like classification of ore deposits is proposed, in which the SZRO have their natural place.