Topical issues of the theory of gold deposit formation

The issues of the theory of gold deposit formation are considered. These issues were crucial in the works by N.V. Petrovskaya. The systematics of gold deposits based on stable mineral assemblages and mineral and geochemical types of ores and their families characteristic of certain groups of gold deposits is consonant with contemporary analogue classifications of ore deposits, which, however, require improvement by means of developing their genetic version. Petrovskaya’s proposed subdivision of gold deposits into families distinguished by depth of their formation is such a version, because in Petrovskaya’s understanding, the factor of depth integrates genetic features of deposits formed at shallow, medium, and great depths. According to recent data, the depth interval of localization of ore deposits is estimated at 15–20 km instead of 6–10 km suggested earlier; thus, the intervals of medium and great depths increase. Attention is called to the Petrovskaya’s ideas of stadial progressive development of ore formation with change in pyrite-arsenopyrite mineralization by base-metal and telluride mineralization along with advanced and concomitant deposition of quartz. The stadial formation of shallow-seated deposits and colloidal mineral formation therein, as well as the concept of gel metasomatism and mechanisms of accompanying destruction of preceding mineral assemblages developed by Petrovskaya, are considered and their implications are illustrated by specific deposits. Petrovskaya’s views on sources of ore matter and the polygenetic character of gold and Au-bearing deposits are discussed.