The leading role of discontinuous and fracture tectonics in localization and location of piezoquartz deposits in the territory of the crystal province of the Subpolar Urals, as well as ore bodies - crystal nests - within the deposits, has been repeatedly noted by researchers...

The considered article by P. B. Vainerman and A. S. Smirnova, in our opinion, insufficiently objectively, and in some cases geologically incorrectly reflects some questions of conditions of formation and regularities of location of Transcaucasian deposits of technical agate. In this regard, we consider it necessary to discuss these iss.s in order to exclude subjective and poorly grounded ideas, which can misdirect researchers ...

Endogenous deposits of technical agate are rare. Geologically they are poorly studied and many questions of conditions of their formation remain unclear. One of such questions concerns the problem of influence of host rocks on the process of formation of deposits of this type of mineral raw material. Geologists who studied endogenous agate deposits, usually note one side of the influence of host rocks: host rocks by virtue of lithological and textural features contributed to the deposition of chalcedony from hydrothermal solutions. At the same time, as a matter of course, it is assumed that the main mass of components, including silica, necessary for crystallization of chalcedony and accompanying minerals, hydrothermal solutions brought to the host rocks from the magmatic hearth ...