Description: Murmanite Peninsula Kola, (probably the Lovozero Massif), Russia FoV= 4 x 3 cm; crystal: 1,5 x 0,5 cm MURMAINTE is a titanium and niobium containing sorosilicate, closely related in composition and structure with Epistolite and Vuonnemite, both of which are already pictured above in the this string. On fresh surfaces the he color is more pinkish than here. I would like to highlight the lustre of this mineral, subtle and difficult to describe, mindat calls it “greasy, pearly” other sources use the wording “silverlike”. Altogether this is a good reminder of the diversity of lustres in the mineral kingdom that we should experience directly and not only through the limited expressions for lustre in language. As for the genesis, Murmanite belongs to a category of minerals that are not crystallized from melts or solutions, but form exclusively by transformation of other phases. (Khomyakov library(.)iem(.)ac(.)ru(/)exper(/)v10_1(/)49(.)pdf)

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