cas·​tor·​ite | \ ˈkastəˌrīt, -ˈaa-, -ˈai-, -ˈȧ- \
variants: or castor \ -​tə(r) How to pronounce castor (audio) \
plural -s

Definition of castorite

: a mineral consisting of a variety of petalite occurring in transparent crystal

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History and Etymology for castorite

castorite from German kastor (from Kastor mythological personage, from Latin Castor) + English -ite; castor from German kastor; from its appearance with pollucite (previously called pollux)

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Cite this Entry

“Castorite.” Dictionary, Merriam-Webster, Accessed 20 Sep. 2020.

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