Abstract:
It has been revealed that in rhythmic-stratified ore-bearing mainly quartz veins and lens-shaped bodies of gold, silver, tin, tungsten, molybdenum, tantalum, fluorite ore deposits of low- and middle-hypogene formations the ore-forming minerals are clastered into regularly interbanded tri-layered structures or «triads» of layers parallel to contacts of veins. The relatively early layer of each triad consists of silicates and alumosilicates (feldspars, early generation tourmaline, phyllosilicates and mixed-layer silicates, in different ratios, etc), the subsequent layer includes ore-minerals (native metals and their solid solutions, sulfides, tellurides, sulfosaults, wolframates, tantalates, metal oxides and halides, some silicates). The triad is completed by quartz, as well as by topaz, in quartz-topaz veins of tin and tungsten ore deposits. There are distinguished mono- and polytriad veins. The consequence in segregation of minerals within triads, and of the mere triads themselves, depends on changes of conventional potential of ionization, concentrations and temperature. Thus, an assumption is made that polytriad veins are formed as a result of unceasing-intermittent crystallization of minerals in consequence of revocable-onward reduction of temperature, quantized outflow of energy, periodical interchange of acidity-alkalinity and concentrations within high-gradient mineral-forming systems.