blue·​schist | \ ˈblü-ˌshist How to pronounce blueschist (audio) \
plural blueschists

Definition of blueschist

geology : a metamorphic rock that is formed under high pressure and low temperature and is characterized by the presence of glaucophane Also radiometric ages of blueschists from the same regions cluster around 400-500 Myr.— T. Nakajima et al., Nature, 19 July 1990 At this depth, where the pressure is 15 to 20 kilobars and temperatures reach about 500 degrees C, rocks called blueschists and eclogites form.— Ian Anderson, New Scientist, 29 Mar. 1997

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First Known Use of blueschist

1789, in the meaning defined above

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The first known use of blueschist was in 1789

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Cite this Entry

“Blueschist.” Dictionary, Merriam-Webster, Accessed 7 Mar. 2021.

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