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Limestone was also a very popular building block in the Middle Ages in the areas where it occurred, since it is hard, durable, and commonly occurs in easily accessible surface exposures. Many medieval churches and castles in Europe are made of limestone. Beer stone was a popular kind of limestone for medieval buildings in southern England. [109]
Natural hydraulic lime (NHL) is made from a limestone which naturally contains some clay. Artificial hydraulic lime is made by adding forms of silica or alumina such as clay to the limestone during firing, or by adding a pozzolana to pure lime. [13] Hydraulic limes are classified by their strength: feebly, moderately and eminently hydraulic ...
The layers have very distinct banded successions that are made up of iron rich layers that alternate with layers of chert. Iron formations are often associates with dolomite, quartz-rich sandstone, and black shale. They sometimes grade locally into chert or dolomite. They can have many different textures that resemble limestone.
Ironstone (sandstone with iron oxides) from the Mississippian Breathitt Formation, Mile Marker 166, I-64, Kentucky. Ironstone is a sedimentary rock, either deposited directly as a ferruginous sediment or created by chemical replacement, that contains a substantial proportion of an iron ore compound from which iron (Fe) can be smelted commercially.
Banded iron formation – Layered iron-rich sedimentary rock; Breccia – Rock composed of angular fragments; Calcarenite – Type of limestone that is composed predominantly of sand-size grains; Chalk – Soft carbonate rock; Chert – Hard, fine-grained sedimentary rock composed of cryptocrystalline silica
Ashford Black Marble – dark limestone quarried in Derbyshire, England. (not a "true marble"; Carboniferous limestone) Bath stone – Oolitic limestone from Somerset used as a building material; Beer Stone – Man-made caves in Devon, England
Travertine (/ ˈ t r æ v ər t iː n / 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.
Common marble varieties are granular limestone or dolomite. The hardness of marble is very high, because the internal structure of the rock is very uniform after long-term natural aging, and the internal stress disappears, so the marble will not be deformed due to temperature, and has strong wear resistance. It is a very popular building material.