Kamenevite
Kamenevite is an IMA-recognized mineral species in the silicate class, with the chemical formula K₂TiSi₃O₉·H₂O.
It crystallizes in the orthorhombic crystal system (space group P2_12_12_1). It is a member of the Umbite structural group.
Key properties: Mohs hardness 4; specific gravity 2.69; White streak; Vitreous luster; optically biaxial.
IMA symbol Kne, IMA status: approved, named in 2017.
A late-stage hydrothermal mineral in K-rich peralkaline pegmatites related to rischorrites in association with apatite-nepheline rocks.
It is found associated with Lomonosovite, aegirine, lamprophyllite, pectolite, shafranovskite, ershovite, lovozerite.
The mineral was named to honor Russian geologist Evgeniy Arsenievich Kamenev (1934-2017) for his contribution to the geological study and exploration of the Khibiny complex apatite deposits.