magnetite

Russia, Amur Region, Mikhailovsky Pillars. Andesites - dark gray, greenish-gray rocks, with a massive, fluid texture. Porphyry phenocrysts up to 20%. Consist: andesine, hornblende, augite. Bulk - volcanic glass. Lower Cretaceous. Determination of absolute age - 115 million years.

Russia, Khabarovsk Territory. Massif quartz diorite. Intense impregnation of a fine ore mineral with a metallic sheen. Magnetite or ilmenite. Upper Cretaceous.

Russia, Khabarovsk Territory. Quartz diorite porphyry. Upper Cretaceous. Consist: quartz 10-15%, plagioclase 60-65%, hornblende 15-25%, biotite up to 5%. Plagioclase - andesine or labrador-andesine. Accessory: magnetite, apatite, sphene.

Russia, Khabarovsk Territory. Dyke alaskite granite. Paleocene. Consist: quartz 30-38%, K-spar 40-55%, plagioclase 15-25%, biotite up to 3%. Plagioclase - oligoclase, rare - oligoclase-albite, albite. Accessory: magnetite, zircon, apatite, monazite. Silicate analysis: SiO₂ 74-77%, TiO₂ 0.1-0.2%, Al₂O₃ 13-14%, Fe₂O₃ 0.3-0.5%, FeO 0.7-1.6%, MnO 0.01-0.04%, MgO 0.1-0.3%, CaO 0.2-0.5%, Na₂O 2.7-3.4%, K₂O 4%, SO₃ 0%, P₂O₅ 0-0.03%, CO₃ 0-0.4%.

Russia, Altai, rock "Four brothers". Belokurikhinsky granite massif. Porphyry biotite granites. Medium grained. Porphyry phenocrysts - microcline. Consist: microcline - 35-65%, plagioclase - 10-30%, quartz 20-30% biotite - 4-7%. Accessory: magnetite, zircon, apatite, muscovite. Upper Permian - Low Triassic.

Russia, Altai, mount Round. Belokurikhinsky granite massif. Porphyry biotite granites. Medium grained. Porphyry phenocrysts - microcline. Consist: microcline - 35-65%, plagioclase - 10-30%, quartz 20-30% biotite - 4-7%. Accessory: magnetite, zircon, apatite, muscovite. Upper Permian - Low Triassic.

Russia, Altai, mount Round. Belokurikhinsky granite massif. Porphyry biotite granites. Medium grained. Porphyry phenocrysts - microcline. Consist: microcline - 35-65%, plagioclase - 10-30%, quartz 20-30% biotite - 4-7%. Accessory: magnetite, zircon, apatite, muscovite. Upper Permian - Low Triassic.

Russia, Altai, mount Tserkovka. Belokurikhinsky granite massif. Porphyry biotite granites. Medium grained. Porphyry phenocrysts - microcline. Consist: microcline - 35-65%, plagioclase - 10-30%, quartz 20-30% biotite - 4-7%. Accessory: magnetite, zircon, apatite, muscovite. Upper Permian - Low Triassic.

Russia, Magadan region, cape Chirikova. Magadan massif of granodiorites. Size - 40 * 45 km. Granodiorites hornblende-biotite. Consist: andesine 50%, anorthoclase 15%, quartz 20%, biotite 7%, green hornblende 5%, monoclinic pyroxene 0,5%. Accessory: chlorite, epidote, zoisite, sphene, zircon, apatite, magnetite. Low Cretaceous.

Russia, Magadan region, cape Chirikova. Magadan massif of granodiorites. Size - 40 * 45 km. Granodiorites hornblende-biotite. Consist: andesine 50%, anorthoclase 15%, quartz 20%, biotite 7%, green hornblende 5%, monoclinic pyroxene 0,5%. Accessory: chlorite, epidote, zoisite, sphene, zircon, apatite, magnetite. Low Cretaceous.