füllosilikaadid

Füllosilikaadid, also known as framework silicates, represent a major group of silicate minerals characterized by a three-dimensional framework of interconnected SiO4 tetrahedra. In these structures, all four oxygen atoms of each tetrahedron are shared with neighboring tetrahedra, forming a robust, open network. This unique arrangement results in minerals with generally high hardness and density.

The most prominent examples of füllosilikaadid are the feldspars, which are the most abundant mineral group in the Earth's crust. Feldspars are further divided into alkali feldspars (like orthoclase and microcline, containing potassium) and plagioclase feldspars (a solid solution series ranging from albite, rich in sodium, to anorthite, rich in calcium). Another significant member of this group is quartz (SiO2), which is composed solely of interconnected SiO4 tetrahedra. Füllosilikaadid often exhibit well-formed crystals and are common constituents of igneous, metamorphic, and sedimentary rocks. Their chemical composition can be complex, often including aluminum, alkali metals (sodium, potassium), and alkaline earth metals (calcium, barium) substituting for silicon within the framework. The specific arrangement and composition of füllosilikaadid influence their physical properties, such as cleavage, color, and optical characteristics.