Kataranskite

Kataranskite is an ornamental and semi-precious stone of lilac color (ranging from light lilac to almost inky violet), hence its other name, “sirenevite”. It is a pseudomorph of plagioclase, completely replaced by aggregates of secondary minerals, primarily finely flaked sericite. 

It was first found in 1904 at the Kataranskii Cape, hence the name, Kataranskite. The only occurrence of kataranskite is located on the Kola Peninsula, on the shore of the White Sea.