neptunite


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neptunite

[′nep·tə‚nīt]
(mineralogy)
(Na,K)2(Fe,Mn)TiSi4O12 Black mineral composed of silicate of sodium, potassium, iron, manganese, and titanium.
References in periodicals archive ?
A faceted Neptunite is so uncommon that GIA featured the Ophir Neptunite in an article published in 2013.