Polylithionite, boromuscovite and borocoockeite.

Three unfrequent minerals from the Sosedka pegmatite, Malkhan, Zabaykalsky, Russia. Malkhan is known for its beautiful red tourmalines. But it is also produces polylithionite. It is accompanied by a powdery mass of boromuscovite and borocoockeite. Boron replaces here the aluminium in the silicate lattice. UV-C @275 nm