polyesteripinnoite
Polyesteripinnoite is a rare mineral species discovered in 2013. It is a complex silicate mineral with the chemical formula (Na,K)2Ca2(Si,Al)8O20(OH,F)2. The mineral was first identified in the Ilimaussaq complex in Greenland, where it occurs as small, colorless to white crystals. Polyesteripinnoite is named for its chemical composition, which includes polyester and innoite, two other minerals found in the same complex.
The mineral's structure is characterized by a framework of silica tetrahedra, with sodium, potassium, and calcium
The mineral's discovery and characterization have provided valuable insights into the complex mineralogy of the Ilimaussaq