Ponomarevite is a mineral that belongs to the eudialyte group. It is a complex silicate mineral comprising several elements, including sodium, calcium, rare earth elements, zirconium, and occasionally titanium. Its chemical formula is primarily Na15Ca(REE,Sr,Na)3Zr3Zr3SiSi[Si6O18](O,O,F,OH)4, although it can vary slightly based on the specific composition.
Ponomarevite typically occurs as small, prismatic crystals that are translucent to opaque. It commonly exhibits a reddish-brown to brown color, with a vitreous to greasy luster on its surfaces. The mineral can also display various shades of yellow, orange, and black. Ponomarevite has a Mohs hardness ranging from 5 to 6, indicating moderate hardness.
This mineral is primarily found in alkaline pegmatites, which are coarse-grained igneous rocks. It commonly occurs in association with other minerals like aegirine, nepheline, lamprophyllite, and arfvedsonite. Ponomarevite has been discovered in several locations worldwide, including Russia, Greenland, Canada, Sweden, and Ukraine.
The name "ponomarevite" was given in honor of Alexandr Pavlovich Ponomarev (1905–1973), a prominent Russian mineralogist and petrologist. Ponomarev made significant contributions to the understanding of alkaline rocks and their associated mineral assemblages. His work helped advance the knowledge of mineralogy and geology, leading to the identification and characterization of minerals such as ponomarevite.
