\ˈchərt, ˈchat \

Definition of chert 

: a rock resembling flint and consisting essentially of a large amount of fibrous chalcedony with smaller amounts of cryptocrystalline quartz and amorphous silica

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Other Words from chert

cherty \ˈchər-​tē, ˈcha-​ \ adjective

Examples of chert in a Sentence

Recent Examples on the Web

The 150-foot-long and 75-foot-tall surface is one of the largest chert slickensides exposures in California. Thomas Graham,, "Walking these seven hills of San Francisco a peak experience," 28 June 2018 And in his final moments, the Iceman ran out of chert to fix his tools. Nicholas St. Fleur, New York Times, "The Final Hours of the Iceman’s Tools," 21 June 2018 The chert that Otzi used was mined from three different areas, which were as far as 40 miles away, Dr. Wierer said. Nicholas St. Fleur, New York Times, "The Final Hours of the Iceman’s Tools," 21 June 2018 His antler retoucher, for instance, bore the scars of striking chert at an oblique angle in the direction a right-handed flintknapper would use. Kiona N. Smith, Ars Technica, "Ötzi the Iceman spent his last days trying to repair his tools," 22 June 2018 The blade was made of a hard, dark rock called chert that is similar to flint. Nicholas St. Fleur, New York Times, "The Final Hours of the Iceman’s Tools," 21 June 2018 At Middle and Lower Paleolithic sites across Europe and the Middle East, for example, archaeologists have found several flint and chert flakes with lines etched into the stones' chalky outer layer—the cortex. Kiona N. Smith, Ars Technica, "Neanderthals etched a message on this 36,000-year-old stone tool," 3 May 2018 At sites older than BOK-2, occupants made their tools out of local volcanic rock, with exotic materials like obsidian and green, white, or brown chert showing up less than eight percent of the time. Kiona N. Smith, Ars Technica, "Unstable climate forced early humans to be more social and creative," 18 Mar. 2018 For instance, the Mars 2020 fossil hunters will look for chert and silica—two types of minerals that, on Earth, are ideal for entombing and preserving biological material. National Geographic, "NASA’s Bold Plan to Hunt for Fossils on Mars," 17 Oct. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'chert.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of chert

1679, in the meaning defined above

History and Etymology for chert

origin unknown

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Statistics for chert

Last Updated

2 Nov 2018

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Time Traveler for chert

The first known use of chert was in 1679

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More from Merriam-Webster on chert

Rhyming Dictionary: Words that rhyme with chert Encyclopedia article about chert

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to enclose within walls

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