noun ber·trand·ite \ˈbər-trən-ˌdīt\

Definition of bertrandite



  1. :  a mineral Be4Si2O7(OH)2 consisting of a beryllium silicate occurring in hard colorless or pale-yellow prismatic crystals (hardness 6–7, specific gravity 2.59–2.60)

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Origin and Etymology of bertrandite

French, from E. Bertrand, 19th century Frenchman who first described it + French -ite

Seen and Heard

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to cast off or become cast off

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