These emerald mines are situated on the Eastern slope of the Urals, 70 kilometers NNE of Sverdlovsk town. The deposit is a complex of metamorphic rocks enclosed by three intrusions, viz.—on the E, by an intrusion of porphyritic granite, on the W, by one of granite, on the E, by the so-called "Eastern“ intrusion — complex and strongly differentiated. The metamorphic complex presents a thick layer of amphibolites and plagioclasehylobites, wherein are included lens-like talcous rocks. In the nuclei of the latter are often to be found remnants of serpentinites and sometimes of peridotites and dunites. In these lenses, through injection of divers vein substrates, have been formed deposits of emeralds, beryl, and fluorite. Porphyritic granite (fig. 1) and granite (fig. 2) are in the main similar rocks. They are made up of quartz, feldspar, and plagioclase, with an insignificant admixture of micas (p. 198). This comparison clearly shows that these two rocks having a great general resemblance greatly differ in details. Therefore it is impossible, to my opinion, to unite them into one integral whole neither from the point of view of their composition nor from the conditions and time of their formation. On the contrary one must recognize that these two rocks are different in all respects.