quartz

Russia, Komi Republic, Subpolar Ural, Big Lemva river. Pink-gray, fine-grained, subalkaline biotite granites. Lemvinsky granite massif. Consist: quartz - 29%, plagioclase - 23%, K-spar - 47%, biotite - 1%. Accesory: zircon, magnetite, sphen, apatite, ortit, ilmenite. Neoproterozoic.

Russia, Khanty-Mansiysk autonomous okrug, Subpolar Ural, Petravozh creek. Gray-green siltstones, sandstones with dykes gabbro. Sedimentary rocks consist: quartz, feldspar, sericite, chlorite. Accesory: hematite, magnetite, leicocsen, zircon, epidote. Fossil: Aristocystites (?) sp., Fascicrinus cf. foliacens Mil sp. nov., Pentagonocyclicus cf. concentricus Yelt., Veryhachium trisulcum Downie Baltisphaeridium longispinosum Ets. Pogureyskaya series. Cambrian (Furongian) - Lower Ordovican (Tremadocian). Dykes gabbro: Upper Ordovican - Lower Silurian.

Russia, Komi Republic, Subpolar Ural, upper reaches of the Little Lemva river. Gray-green siltstones. Consist: quartz, feldspar, sericite, chlorite. Accesory: hematite, magnetite, leicocsen, zircon, epidote. Fossil: Aristocystites (?) sp., Fascicrinus cf. foliacens Mil sp. nov., Pentagonocyclicus cf. concentricus Yelt., Veryhachium trisulcum Downie Baltisphaeridium longispinosum Ets. Pogureyskaya series. Cambrian (Furongian) - Lower Ordovican (Tremadocian).

Russia, Sakha Republic (Yakutia), Gross gold deposit, upper Usu river. Metasomatically modified polymictic sandstones of the olonnokon series with quartz veins. Gold ore. Paleoproterozoic. 

Russia, Chita region, Pogromnoye gold deposit. Albite-sericite-quartz metasomatite with quartz and carbonate-quartz veins and interspersed with arsenopyrite. Gold ore. Gold - 8.3 g/t. Upper Jurassic.

Russia, Chita region, Pogromnoye gold deposit. Carbon siltstones with quartz veins. Ikagiyskaya series. Lower Jurassic.

Russia, Sakha Republic (Yakutia), Tabornoye gold deposit, upper Usu river. Metasomatically modified polymictic sandstones of the olonnokon series with quartz veins. Gold ore. Paleoproterozoic. 

Russia, Sakha Republic (Yakutia), Tabornoye gold deposit, upper Usu river. Metasomatically modified polymictic sandstones of the olonnokon series with quartz veins. Contain gold. Paleoproterozoic. 

Russia, Magadan region, left side of the Duck river. Quartz-albite diorite porphyrite with quartz-albite veins. These are the famous Ducks dykes. Dyke №7. The dyke is a slab-like body with a capacity of 0.5 m in the East to 3.5 m in the West, accompanied by apophyses that run parallel to the sedimentary rocks (lower Jurassic siltstone). It is traced to a depth of 250 meters. Xenoliths are rare. Sometimes there are intersecting, until the disappearance of dykes.

Russia, Magadan region, left side of the Duck river. Quartz-feldspar siltstones. Lower Jurassic.