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Troctolite – Igneous rock – A plutonic ultramafic rock containing olivine, pyroxene and plagioclase; Trondhjemite – Light-colored intrusive igneous rock – A form of tonalite where plagioclase-group feldspar is oligoclase; Tuff – Rock consolidated from volcanic ash; Vitrophyre – Glassy volcanic rock - Glassy igneous rock with phenocrysts
There is no precise definition of the term, although its roots go to antiquity, [2] when it was used to designate any porous building rock, [3] regardless of its origin, [4] mostly in contrast with marble. In the 20th century the archeologists continued to use the term in the similarly loose way: "poros [was] made to include almost all light ...
Oolite – Sedimentary rock formed from ooids; Rag-stone – Work done with stones that are quarried in thin pieces; Shelly limestone – Limestone containing many fossils; Travertine – Form of limestone deposited by mineral springs; Tufa – Porous limestone rock formed when carbonate minerals precipitate out of ambient temperature water
The air-filled vesicles in this porous rock serve as a good insulator. [18] A fine-grained version of pumice called pozzolan is used as an additive in cement and is mixed with lime to form a light-weight, smooth, plaster-like concrete. This form of concrete was used as far back as Roman times.
Tufa columns at Mono Lake, California. Tufa is a variety of limestone formed when carbonate minerals precipitate out of water in unheated rivers or lakes. Geothermally heated hot springs sometimes produce similar (but less porous) carbonate deposits, which are known as travertine or thermogene travertine.
The stone is porous, and often yellow in color. It is also found in Kaliana village (Charkhi Dadri district, Haryana, India), [1] the U.S. state of Georgia, and Stokes and McDowell counties of North Carolina. It is the best and most widely known example of a flexible sandstone, and is a source of diamonds found in the Minas Gerais area of ...
Carboniferous Limestone is a hard sedimentary rock made largely of calcium carbonate. It is generally light-grey in colour. It was formed in warm, shallow tropical seas teeming with life. The rock is made up of the shells and hard parts of millions of sea creatures, some up to 30 cm in length, encased in carbonate mud.
Gneiss (/ n aɪ s / 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.