Chert (/ˈtʃɜːrt/) is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide...

57°20′12″N 002°50′29″W / 57.33667°N 2.84139°W / 57.33667; -2.84139 The Rhynie chert is a Lower Devonian sedimentary deposit exhibiting extraordinary fossil...

is made up of three formations, the Grassy Knob Chert, the Backbone Limestone and Clear Creek Chert. It is Lower Devonian in age. Eastward the group...

microorganisms permineralized in 3.465-billion-year-old Australian Apex chert rocks. However, the evidence for the biogenicity of these microstructures...

white chert. Facies 3, which overlies facies 2, consists largely of centimeter-layered chert. The layered chert consists of white-gray layered chert and...

and William H. Lang in 1917. The species is known only from the Rhynie chert in Aberdeenshire, Scotland, where it grew in the vicinity of a silica-rich...

The Bigfork Chert is a Middle to Late Ordovician geologic formation in the Ouachita Mountains of Arkansas and Oklahoma. First described in 1892, this...

The Huntersville Chert or Huntersville Formation is a Devonian geologic formation in the Appalachian region of the United States. It is primarily composed...

The Gunflint chert (1.88 Ga) is a sequence of banded iron formation rocks that are exposed in the Gunflint Range of northern Minnesota and northwestern...

Clifty Limestone is very sandy, light blue to bluish grey. The Penters Chert is a Devonian geologic formation in the Ozark Plateaus of Arkansas. Its...

partial head with preserved mouthparts from the Early Devonian aged Rhynie chert around 400 million years ago, when Earth’s first terrestrial ecosystems...

Radiolarite is a siliceous, comparatively hard, fine-grained, chert-like, and homogeneous sedimentary rock that is composed predominantly of the microscopic...

The Princeton Chert is a fossil locality in British Columbia, Canada, which comprises an anatomically preserved flora of Eocene Epoch age, with rich species...

experienced low-grade metamorphism.  Other important lithologies include chert, basalt, limestone, serpentinite, and high-pressure, low-temperature metabasites...

Mill Creek chert is a type of chert found in Southern Illinois and heavily exploited by members of the Mississippian culture (800 to 1600 CE). Artifacts...

surfaces of the chert, totally weathered out of the chert, and as hollow chert casts of the acorns. A total of 42 specimens in chert were studied by paleobotanists...

typically has a contrasting composition, such as a pyrite nodule in coal, a chert nodule in limestone, or a phosphorite nodule in marine shale, from the enclosing...

03694°W / 40.09750; -112.03694 Discovery 1960 (by Dale Green) Geology Chert Entrances 1 Difficulty Slippery Hazards Slippery and Tight Access Closed...

Devonian fossil assemblage from the Rhynie chert. These early plants were preserved by being petrified in chert formed in silica-rich volcanic hot springs...

cryptocrystalline form of the mineral quartz, categorized as the variety of chert that occurs in chalk or marly limestone. Historically, flint was widely...

In 2014, a chert manuport was discovered embedded in an ancient reef on Barrow Island, Western Australia. The island has no natural chert deposits and...

Oxidation Event or snowball earths. The red bands are microcrystalline red chert, also called jasper. Picture jaspers exhibit combinations of patterns resulting...

from diatom-rich plankton, became diatomites, porcelainites, and banded cherts. The Monterey formation has long been recognized as the primary source of...

semi-translucent light-grey stone with dark banding called "Ramah chert". The Ramah chert outcrops in a narrow geological bed stretching from Saglek Fiord...

species is known from permineralized remains recovered from the Princeton Chert in British Columbia, Canada. Rhizomes of Dickwhitea are noted for having...

Early Eocene Princeton Chert in British Columbia, Canada. Allenbya collinsonae is known exclusively from the Princeton Chert, a fossil locality in British...

mainly of the Liminangcong Formation, a Permian to Late Jurassic chert. This chert forms the distinguishing mountain ranges, with the Middle-Late Jurassic...

mainly of the Liminangcong Formation, a Permian to Late Jurassic chert. This chert forms the distinguishing mountain ranges, with the Middle-Late Jurassic...

The Nuvvuagittuq Greenstone Belt (NGB; Inuktitut: [nuv.vu.a.git.tuq]) is a sequence of metamorphosed mafic to ultramafic volcanic and associated sedimentary...

del Consell, pel qual s’aprova el canvi de denominació del municipi de Chert/Xert per la forma exclusiva en valencià de Xert. [2014/6338] DOCV. Generalitat...