Quartzite

Russia, Caucasus, Kabardino-Balkarian Republic, Adyrsu River Gorge. Gondarayskiy metamorphic complex, verkhnebalkarsky metamorphic subcomplex. Muscovite, biotite, feldspathic, hornblende gneisses; chlorite-hornblende, quartz-hornblende, quartz-tremolite schists; migmatitized gneiss and schists, migmatitis. Sometimes quartzite. Fine-grained, medium-grained. Proterozoic, mesoproterozoic.

Russia, Caucasus, Kabardino-Balkarian Republic, Adyrsu River Gorge. Gondarayskiy metamorphic complex, verkhnebalkarsky metamorphic subcomplex. Muscovite, biotite, feldspathic, hornblende gneisses; chlorite-hornblende, quartz-hornblende, quartz-tremolite schists; migmatitized gneiss and schists, migmatitis. Sometimes quartzite. Fine-grained, medium-grained. Proterozoic, mesoproterozoic.

Russia, Caucasus, Kabardino-Balkarian Republic, Adyrsu River Gorge. Gondarayskiy metamorphic complex, verkhnebalkarsky metamorphic subcomplex. Muscovite, biotite, feldspathic, hornblende gneisses; chlorite-hornblende, quartz-hornblende, quartz-tremolite schists; migmatitized gneiss and schists, migmatitis. Sometimes quartzite. Fine-grained, medium-grained. Proterozoic, mesoproterozoic.

Russia, Caucasus, Karachay-Cherkess Republic, Khasaut River Valley. Gray, lilac-gray quartzites and arkose sandstones. Silurian. Llandovery (?)

In the first photo, in the background (distant cliffs) -  Light gray quartz and polymictic sandstones, with mudstones, siltstones and interbeds of coal. Fossil: Velopecten rollei Tate, Lima punctata Sow., Circostylus euomphalus Quenst., Leda (Dacryomya) cf. graphica Tate, Astarte subtetragona Minst., Parallelodon aff. similis Terq., Hinnites sp. ind. (cf. davoei  Dam),  Nucula cf. palmae Sow. Lower Jurassic. Pliensbachian.

Russia, Caucasus, Karachay-Cherkess Republic, Khasaut River Valley. Gray, lilac-gray quartzites and arkose sandstones. Silurian. Llandovery (?)

Migmatized quartz-biotite schists. Srednegudzhal'skaya series. Thickness - 1200-1400 metres. Absolute definition of age - no. Fossil - no. Pr₁gd_2.

Russia, Khabarovsk Territory, the valley of the creek Elovy. Quartzites with veins of quartz. Srednegudzhal'skaya series. Thickness - 1200-1400 metres. Absolute definition of age - no. Fossil - no. Pr₁gd_2. ICP quartz vein: Al - 6.69%, As - 3 ppm, Ba - 363 ppm, Be  - 0.9 ppm, Ca - 0.52%, Cd - 10 ppm, Co - 114 ppm, Cu - 2.5 ppm, Fe - 0.91%, K - 2.68%, La - 8.1 ppm, Li - 13 ppm, Mg - 0.32%, Mn - 342 ppm, Na - 1.35%, Ni - 6 ppm, Pb - 49 ppm, Sc - 4.6 ppm, Sr - 92.6 ppm, Ti - 0.1%, V - 19 ppm, W - 530 ppm, Y - 11 ppm, Zn - 26.6 ppm, Zr - 23.7 ppm. 

Tectonic fault zone in quartzites. Srednegudzhal'skaya series. Thickness - 1200-1400 metres. Absolute definition of age - no. Fossil - no. Pr₁gd₂. Spectral analysis: Ag - 0.04-0.1 g/t, As - 0,003%, Cu - 0,0025 - 0,008%, Bi - 0,00013%, Co - 0,0013 - 0,003%, Cr - 0,008 - 0,013%, Li - 0,0025 - 0,004%, Mn - 0,004 - 0,08%, Mo - 0,00025 - 0,0004%, Ni - 0,0025 - 0,008%, Pb - 0,0008 - 0,0013%, Sn - 0,00025%, V - 0,008 - 0,018%, W - 0,0013 - 0,01%, Zn - 0,006%, Au - 0.006 g/t

Khabarovsk Territory, Gujal river valley. Quartzites with veins of quartz. Srednegudzhal'skaya series. Thickness - 1200-1400 metres. Absolute definition of age - no. Fossil - no. Pr₁gd_2. Spectral analysis quartz vein: Ag - 0,000004%, As - 0,003%, Cu - 0,0025%, Co - 0,06%, Cr - 0,025%, Li - 0,01%, Mn - 0,03%, Mo - 0,0025%, Ni - 0,008%, Sb - 0,0025%, V - 0,003%, W - 1%, Zn - 0,004%.

Russia, Sakhalin, Chekhov peak. Quartzites, hematite quartzites, slates. Green shale formation. Krasnosel'skaya metamorphic series. Upper Cretaceous. asK₂kr.