amphibole group


: a group of minerals (as anthophyllite, tremolite, actinolite, and hornblende) with essentially like crystal structures involving a silicate chain [OH(Si4O11)]n and generally containing three groups of metal ions, the large ions being sodium and calcium, the intermediate being chiefly bivalent iron, magnesium, and manganese, and the small ions chiefly silicon with some aluminum and rarely ferric iron, the general formula for the group being A2B5(Si, Al)8O22(OH) 2

Word History

First Known Use

1828, in the meaning defined above

Time Traveler
The first known use of amphibole group was in 1828

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Dictionary Entries Near amphibole group

Cite this Entry

“Amphibole group.” Dictionary, Merriam-Webster, Accessed 26 Mar. 2023.

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