Sharp yellow crystals of the very rare mineral fluorlamprophyllite (IMA 2013-102) from the type locality (Morro do Serrote, Cascata, Minas Gerais, Brazil) and only known locality worldwide. — Photo: David Hospital · CC BY-SA 4.0
Fluorlamprophyllite
Fluorlamprophyllite is an IMA-recognized mineral species in the silicate class, with the chemical formula (SrNa)Ti₂Na₃Ti(Si₂O₇)₂O₂F₂.
It crystallizes in the monoclinic crystal system. It is a member of the Seidozerite-Lamprophyllite structural group.
Key properties: Mohs hardness 3; specific gravity 3.484; Pale yellow streak; Adamantine luster; optically biaxial.
IMA symbol Flmp, IMA status: approved, named in 2013.
Embedded in nepheline syenite in an alkaline massif.
It is found associated with Aegirine, analcime, natrolite, nepheline, microcline.
The fluorine-analogue of lamprophyllite.