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malladrite

noun mal·la·drite \ məˈläˌdrīt , ˈmaləˌd- \
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Definition of malladrite

plural -s
: a sodium fluosilicate Na2SiF6 occurring in minute hexagonal crystals in fumaroles in the crater of Vesuvius near Naples in Italy

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Origin and Etymology of malladrite

Italian, from Alessandro Malladra †1944 Italian geologist + Italian -ite

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