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The marbled salamander is a stout, black and white banded salamander. It exhibits sexual dimorphism with bands of females tending to be light gray, while those of males are bright white. Males also have a larger proportion of white dorsal surface area relative to females. [2] Females have been reported to have more asymmetrical dorsal markings ...
Calcite alabaster also is known as: onyx-marble, Egyptian alabaster, and Oriental alabaster, which terms usually describe either a compact, banded travertine stone [2] or a stalagmitic limestone colored with swirling bands of cream and brown. [3]
Metamorphic rock, deformed during the Variscan orogeny, at Vall de Cardós, Lérida, Spain. Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than 150 to 200 °C (300 to 400 °F) and, often, elevated pressure ...
Phyllite Banded gneiss with a dike of granite orthogneiss Marble Quartzite Manhattan Schist, from Southeastern New York Slate. Anthracite – Hard, compact variety of coal; Amphibolite – Metamorphic rock type; Blueschist – Type of metavolcanic rock; Cataclasite – Rock found at geological faults – A rock formed by faulting
Gneiss (/ naɪs / nice) is a common and widely distributed type of metamorphic rock. It is formed by high-temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks. This rock is formed under pressures anywhere from 2 to 15 kbar, sometimes even more, and temperatures over 300°C (572°F).
Jasper, an aggregate of microgranular quartz and/or cryptocrystalline chalcedony and other mineral phases, [1][2] is an opaque, [3] impure variety of silica, usually red, yellow, brown or green in color; and rarely blue. The common red color is due to iron (III) inclusions. Jasper breaks with a smooth surface and is used for ornamentation or as ...
A sample of banded hornfels, formed by contact metamorphism of sandstones and shales by a granite intrusion. Hornfels is the group name for a set of contact metamorphic rocks that have been baked and hardened by the heat of intrusive igneous masses and have been rendered massive, hard, splintery, and in some cases exceedingly tough and durable. [1]
Travertine (/ ˈtrævərtiːn / TRAV-ər-teen) [1] is a form of terrestrial limestone deposited around mineral springs, especially hot springs. It often has a fibrous or concentric appearance and exists in white, tan, cream-colored, and rusty varieties. [2][3] It is formed by a process of rapid precipitation of calcium carbonate, often at the ...