noun, often capitalized
eas·​ton·​ite | \ ˈēstəˌnīt \
plural -s

Definition of eastonite

: a mineral K2Mg5AlSi5Al3O20(OH)4 consisting of basic silicate of potassium, aluminum, and magnesium and being an end-member of the biotite system

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History and Etymology for eastonite

Easton, city in eastern Pennsylvania, its locality + English -ite

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Cite this Entry

“Eastonite.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/eastonite. Accessed 11 Jul. 2020.

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