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caswellite

noun
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cas·​well·​ite | \ ˈkazwəˌlīt \
plural -s

Definition of caswellite

: a mineral from Franklin, N.J., consisting of an altered biotite

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History and Etymology for caswellite

John H. Caswell, 19th century American mineralogist + English -ite

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“Caswellite.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/caswellite. Accessed 12 Jun. 2021.

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