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psilomelane

noun psi·lo·mel·ane \ ˌsīlōˈmeˌlān \

Definition of psilomelane

plural -s
:a basic oxide of barium and bivalent and quadrivalent manganese probably BaMnMn8O16(OH)4 — compare hollandite, coronadite

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Origin and Etymology of psilomelane

psil- + -melane

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