chert

noun \ ˈchərt , ˈchat \

|Updated on: 1 Jun 2018

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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cherty

play \ˈchər-tē, ˈcha-\ adjective

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Recent Examples of chert from the Web

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
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.