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Chert (/ tʃ ɜːr t /) is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, [1] the mineral form of silicon dioxide (SiO 2). [2] Chert is characteristically of biological origin, but may also occur inorganically as a chemical precipitate or a diagenetic replacement, as in petrified wood. [3]
Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, [1] [2] categorized as the variety of chert that occurs in chalk or marly limestone. Historically, flint was widely used to make stone tools and start fires. Flint occurs chiefly as nodules and masses in sedimentary rocks, such as chalks and limestones.
Caricature of Napoleon with a chort A Ukrainian disguised as a Czort on Malanka. A chort (Russian: чёрт, Belarusian and Ukrainian: чорт, Serbo-Croatian čort or črt, Polish: czart and czort, Czech and Slovak: čert, Slovene: črt) is an anthropomorphic malign spirit or demon [1] [2] in Slavic folk tradition.
Minerals that typically form nodules include calcite, chert, apatite (phosphorite), anhydrite, and pyrite. [1] [2] Nodular is used to describe a sediment or sedimentary rock composed of scattered to loosely packed nodules in matrix of like or unlike character. It is also used to describe mineral aggregates that occur in the form of nodules, e.g ...
Pages in category "Chert" The following 23 pages are in this category, out of 23 total. This list may not reflect recent changes. ...
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.
Mozarkite is a form of chert . It is the state rock of Missouri. The name is a portmanteau, formed from Mo (Missouri), zark , and ite (meaning rock). [1] Mozarkite consists essentially of silica (quartz - SiO 2) with varying amounts of chalcedony. It has won distinction as a particular form or variety of chert because of its unique variation of ...
Mill Creek Chert is a tough, coarse-grained chert, usually brown or gray in color, and occurs as large tabular shaped nodules. [3] The best archaeological evidence states that maize (corn) first entered the United States from Mexico around 800 CE.