: a dark gray to black dense to fine-grained igneous rock that consists of basic plagioclase, augite, and usually magnetite
Examples of basalt in a Sentence
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The basalt tools include mace-type objects and anvils, which would have been utilized to crack and crush plant foods.
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Newsweek, 8 Jan. 2025
Authorities are urging visitors to stop jamming pocket change between the basalt columns that make up the Giant’s Causeway, a national nature reserve and UNESCO World Heritage Site on the coast of the North Atlantic Ocean.
—Sarah Kuta, Smithsonian Magazine, 4 June 2025
Ancient Tools Show Our Ancestors Ate a Varied Diet
For the study, scientists examined maces and anvils made from basalt, a type of rock formed from rapidly cooling lava at the Earth’s surface, that ancient humans used to crack and crush plant foods.
—Tom Gavin, EverydayHealth.com, 13 Jan. 2025
The lower level is rich in basalt, while the upper level contains a lot of silica.
—Paul Smaglik, Discover Magazine, 3 Jan. 2025
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Newsweek, 8 Jan. 2025
Authorities are urging visitors to stop jamming pocket change between the basalt columns that make up the Giant’s Causeway, a national nature reserve and UNESCO World Heritage Site on the coast of the North Atlantic Ocean.
—Sarah Kuta, Smithsonian Magazine, 4 June 2025
Ancient Tools Show Our Ancestors Ate a Varied Diet
For the study, scientists examined maces and anvils made from basalt, a type of rock formed from rapidly cooling lava at the Earth’s surface, that ancient humans used to crack and crush plant foods.
—Tom Gavin, EverydayHealth.com, 13 Jan. 2025
The lower level is rich in basalt, while the upper level contains a lot of silica.
—Paul Smaglik, Discover Magazine, 3 Jan. 2025
See All Example Sentences for basalt
Cite this Entry
“Basalt.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/basalt. Accessed 18 Jul. 2025.
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: a dark gray to black usually fine-grained igneous rock
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