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Feldspathic sandstones are commonly immature or sub-mature. [1] These sandstones occur in association with cratonic or stable shelf settings. [1] Feldspathic sandstones are derived from granitic-type, primary crystalline, rocks. [1] If the sandstone is dominantly plagioclase, then it is igneous in origin. [1]
A distinction is made between the Upper Greensand and Lower Greensand. The term greensand was originally applied by William Smith to glauconitic sandstones in the west of England and subsequently used for the similar deposits of the Weald, before it was appreciated that the latter are actually two distinct formations separated by the Gault Clay ...
Steenpan (also Flatpan or Klippan), Free State province, near Wolvehoek; Table Mountain Sandstone Western Cape province, various quarry sites; numerous types, some without trade names, from the Karoo Supergroup in many quarries near Graaff-Reinet, Cradock, Queenstown, Aliwal North, Burgersdorp and Sterkstroom; Těšínský sandstone quarry ...
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Flysch (/ f l ɪ ʃ /) is a sequence of sedimentary rock layers that progress from deep-water and turbidity flow deposits to shallow-water shales and sandstones. It is deposited when a deep basin forms rapidly on the continental side of a mountain building episode.
An important industrial use of ganister was as the mouldable monolithic refractory lining or brick lining for the acid Bessemer converter, a steel-making process developed in 1856 in Sheffield, England. The process could not initially be used successfully by steelworks other than Bessemer's though, owing to its need for a low phosphorus iron ore.
Overlying the Millstone Grit sequence is the thick Westphalian sequence of sandstones, mudstones and coal seams collectively referred to as the Pennine Coal Measures Group and which forms the Lancashire Coalfield, the western part of which extends into Merseyside. The youngest Carboniferous strata in the area are the non-productive (of coal ...
Round and oval natural shaped sandstones are sometimes found. Examples made from hornblende gneiss and granitic gneiss were noted, both very difficult stone to work. Granitic rocks were also used; and the famous Towie example from Aberdeenshire may be serpentinised picrite. The highly ornamented examples were mainly made of sandstone or serpentine.