Modern mineralogy of gold: overview and new data

We suppose that it should be useful for archaeologists to have an overview on gold mineralogy, because 1) in ancient times, part of the golden objects were made directly from natural golden nuggets; 2) most of the Au in ores exists as its own minerals. The major part of the Au in the planets and meteorites of our Solar system is found in high temperature solid solutions: metallic Fe-Ni and monosulfides Fe-Ni and Fe-Cu. Au leaves them under fluid or some other reworking. As a result, Au minerals are formed. They are mainly developed in hydrothermal deposits of the upper part of Earth’s continental crust. Au is the noblest chemical element. Thus, the most part of Au in deposits appears as native gold: Au-Ag, Au-Ag-Hg, Au-Cu, Au-Pd, and Au-Pt system minerals. The most important feature of native gold is its fineness, i.e. the Au content in the mineral species, expressed in ‰. Chalcogenides of Au – sulfides and selenides, and, similar to them, tellurides, plumbotellurides, antimonides, bismuthides – are not so widespread. Data on the 44 Au mineral species known today are provided in this overview. The first quantitative estimations of natural native gold nano-dimensional crystallites of several mesothermal deposits are enclosed.