Metamorphic Rocks

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Metamorphic Rocks Pictures of Foliated and Non-Foliated Rock Types Amphibolite is a non-foliated metamorphic rock that forms through Phyllite is a foliate metamorphic rock that is made up mainly of very recrystallization under conditions of high viscosity and directed pressure. fine-grained mica. The surface of phyllite is typically lustrous and It is composed primarily of amphibole and plagioclase, usually with very sometimes wrinkled. It is intermediate in grade between slate and schist. little quartz. The specimen shown above is about two inches (five The specimen shown above is about two inches (five centimeters) centimeters) across. across. Gneiss is foliated metamorphic rock that has a banded appearance and is made up of granular mineral grains. It typically contains abundant Quartzite is a non-foliated metamorphic rock that is produced by the quartz or feldspar minerals. The specimen shown above is about two metamorphism of sandstone. It is composed primarily of quartz. The inches (five centimeters) across. specimen above is about two inches (five centimeters) across. Hornfels is a fine-grained nonfoliated metamorphic rock with no specific Schist is metamorphic rock with well developed foliation. It often composition. It is produced by contact metamorphism. Hornfels is a rock contains significant amounts of mica which allow the rock to split into that was "baked" while near a heat source such as a magma chamber, thin pieces. It is a rock of intermediate metamorphic grade between sill or dike. The specimen shown above is about two inches (five phyllite and gneiss. The specimen shown above is a "chlorite schist" centimeters) across. because it contains a significant amount of chlorite. It is about two inches (five centimeters) across. Marble is a non-foliated metamorphic rock that is produced from the metamorphism of limestone. It is composed primarily of calcium Slate is a foliated metamorphic rock that is formed through the carbonate. The specimen shown above is about two inches (five metamorphism of shale. It is a low grade metamorphic rock that splits centimeters) across. into thin pieces. The specimen shown above is about two inches (five centimeters) across. Novaculite Novaculite is a dense, hard, fine-grained, siliceous rock that Soapstone is a metamorphic rock that consists primarily of talc with breaks with a conchoidal fracture. It forms from sediments deposited in varying amounts of other minerals such as micas, chlorite, amphiboles, marine environments where organisms such as diatoms (single-celled pyroxenes and carbonates. It is a soft, dense, heat-resistant rock that algae that secrete a hard shell composed of silicon dioxide) are has a high specific heat capacity. These properties make it useful for a abundant in the water. The specimen shown above is about three wide variety of architectural, practical and artistic uses. inches across. METAMORPHIC ROCKS Amphibolite Gneiss Hornfels Marble Novaculite Phyllite Quartzite Schist Slate Soapstone .

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