JEREMEJEVITE

Jeremejevite is a rare aluminium borate mineral with variable fluoride and hydroxide ions. Its chemical formula is Al6B5O15(F,OH)3.
It was first described in 1883 for an occurrence on Mt. Soktui, Nerschinsk district, Adun-Chilon Mountains, Siberia. It was named after Russian mineralogist Pavel Vladimirovich Eremeev (Jeremejev, German) (1830–1899).
It occurs as a late hydrothermal phase in granitic pegmatites in association with albite, tourmaline, quartz and rarely gypsum. It has also been reported in the Pamir Mountains of Tajikistan, Namibia and the Eifel district, Germany.