chert

Definitions

  • WordNet 3.6
    • n chert variety of silica containing microcrystalline quartz
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Webster's Revised Unabridged Dictionary
    • n Chert chẽrt (Min) An impure, massive, flintlike quartz or hornstone, of a dull color.
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Century Dictionary and Cyclopedia
    • n chert A cryptocrystalline variety of quartz, also called hornstone, petrosilex, or rock-flint. It is less hard than quartz crystal, has usually a conchoidal or slightly splintery fracture, is commonly gray-brown or black in color, and is often somewhat translucent. It frequently occurs in layers or concretionary nodules, especially in limestone rocks. The name is also applied to any impure flinty rock, including the jaspers.
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Chambers's Twentieth Century Dictionary
    • n Chert chėrt a kind of quartz or flint: hornstone
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Etymology

Webster's Revised Unabridged Dictionary
Ir. ceart, stone, perh. akin to E. crag,
Chambers's Twentieth Century Dictionary
Prob. Celt.; Ir. ceart, a pebble.

Usage

In literature:

Sandstone is the prevailing rock, sometimes passing into jasper, and also into chert and coarse limestone.
"Journals of Australian Explorations" by A C and F T Gregory
The arrow-heads of chert used for hunting are peculiarly fastened, in order to make the arrow revolve.
"My Native Land" by James Cox
Characteristics: flint, chert, obsidian, green and red jasper, and quartz-crystal flakes, arrowheads, cores, and saw-blades.
"How to Observe in Archaeology" by Various
Sometimes this black flint passes into chert and chalcedony of blue and purple tints.
"In Indian Mexico (1908)" by Frederick Starr
Scarcely any chert was included, although it is abundant on the hill; the few pieces seen were very small.
"Archeological Investigations" by Gerard Fowke
Spearheads of chert or flint.
"Illustrated Catalogue of a Portion of the Collections Made" by William H. Holmes
The rest is paved with granite blocks, chert and macadam.
"Atlanta" by Atlanta Chamber of Commerce
In the limestone was found the flint or chert used for weapons and instruments in early times.
"Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 1" by Various
Radiolaria are found in cherts in the Culm of Devonshire and Cornwall, in Russia, Germany and elsewhere.
"Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 3" by Various
A gradual passage from chert to limestone is not uncommon.
"Principles of Geology" by Charles Lyell
It sometimes passes into milk-white chert, which forms beds.
"Narrative of a Second Expedition to the Shores of the Polar Sea" by John Franklin
In the Kapoewas district radiolarian cherts supposed to be of Jurassic age are met with.
"Encyclopaedia Britannica, 11th Edition, Volume 4, Slice 3" by Various
In some of the folds of Arenig cherts diabase lavas appear, which occupy small lenticular areas.
"Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 10" by Various
What is the nature of chert and flint nodules?
"Geology" by James Geikie
Chert, an impure variety of flint.
"A Manual of the Antiquity of Man" by J. P. MacLean
Chert is a coarser and less perfectly homogeneous substance of the same nature and composition as flint.
"Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 5" by Various
Gray chert, fine large flaking, point polished from long use.
"American Antiquities" by Wm. B. Norman
Points were made from Ft. Payne chert, Bangor nodular flint, jasper or other local materials.
"Handbook of Alabama Archaeology: Part I Point Types" by James W. Cambron
He had discussed it with Lil on the comfortable pampas grass above the chert quarry not far from the cottage.
"Mountain" by Clement Wood
The second is made of red jasper and the third of white chert.
"The Archaeology of the Yakima Valley" by Harlan Ingersoll Smith
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In news:

It turns out arrowheads can be made of argillite, chalcedony, chert/flint, diorite, hematite, jasper, rhyolite, siltstone, crystal quartz, quartz, and quartzite.
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In science:

The most complete discussion we found of the c. 3.5 Ga Apex cherts is Brasier, et al.
Astrophysics in 2005
Taking the two papers together, the authors use nonintrusive and non-destructive Raman imagery and confocal laser scanning microscopy of thin slices of precambrian fossils in cherts.
Astrophysics in 2006
Above the cliff face is a younger unit (which we did not study) with sepiolite, chert, marls, etc., forming the white relief seen above from the distance, which is part of the so -called Middle Unit or Intermediate Unit of the Miocene.
The Cyborg Astrobiologist: Testing a Novelty-Detection Algorithm on Two Mobile Exploration Systems at Rivas Vaciamadrid in Spain and at the Mars Desert Research Station in Utah
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