greenstone

American  

[green-stohn] / ˈgrinˌstoʊn /

noun

1. any of various altered basaltic rocks having a dark-green color caused by the presence of chlorite, epidote, etc.

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greenstone British  

/ ˈɡriːnˌstəʊn /

noun

1. any basic igneous rock that is dark green because of the presence of chlorite, actinolite, or epidote

2. a variety of jade used in New Zealand for ornaments and tools

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greenstone Scientific  

/ grēn′stōn′ /

1. Any of various green metamorphic rocks formed from igneous rocks that have a relatively low silica content and owe their color to the presence of a green mineral such as chlorite, hornblende, or epidote.

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Etymology

Origin of greenstone

First recorded in 1765–75; green + stone

Example Sentences

See Examples For:

greenstone

Houses and a “polished greenstone axe” dating to around 3800 B.C. have been excavated at Horton, west of London.

From The Wall Street Journal ● Jan. 23, 2026

The box also held three ceramic vessels, ear flares and a pair of greenstone beads.

From Reuters ● Sep. 25, 2023

Jackson, who once helped evaluate lease blocks in a region of Mali several hundred kilometers away from Bourakébougou, believes greenstone belts deep in the West African craton are driving the hydrogen production there.

From Science Magazine ● Feb. 15, 2023

About 2.7 billion years ago, basalt lava flowed underwater near what’s now the state’s border with Canada; the lava hardened, and the creep of geologic time turned it into a bedrock of greenstone and granite.

From New York Times ● Oct. 12, 2017

The rock near here is greenstone, in which are many veins of pyrites.

From Narrative of the surveying voyages of His Majesty's ships Adventure and Beagle, between the years 1826 and 1836 Volume I. - Proceedings of the First Expedition, 1826-1830 by Robert Fitzroy