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pinnoite

noun
pin·​no·​ite | \ˈpinəˌwīt\
plural -s

Definition of pinnoite 

: a hydrous magnesium borate Mg(BO2)2.3H2O usually occurring in yellow nodular masses with a radiating fibrous structure (hardness 3–4, specific gravity 2.3)

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History and Etymology for pinnoite

German pinnoit, from Pinno, 19th century German mining official + German -it -ite

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