Inosilikatet

Inosilikatet is a silicate mineral group characterized by the presence of double chains of silica tetrahedra. Each tetrahedron consists of a central silicon atom bonded to four oxygen atoms. In the structure of inosilicates, these tetrahedra link together by sharing two of their oxygen atoms with adjacent tetrahedra, forming extended, parallel chains. These chains are then held together by cations, typically metallic ions like iron, magnesium, calcium, and aluminum. The specific arrangement and types of cations present in the crystal lattice determine the properties and classification of individual inosilicate minerals.

The two main subgroups within the inosilicates are the single-chain silicates, also known as pyroxenes, and the double-chain silicates, known as amphiboles. Pyroxenes have a simpler, single-chain structure, while amphiboles exhibit a more complex double-chain arrangement. This structural difference leads to variations in their physical properties, such as cleavage angles and hardness. Many common rock-forming minerals belong to the inosilicate group, playing significant roles in the Earth's crust and mantle. Examples include olivine, quartz, and feldspar, though olivine is actually a nesosilicate, and quartz and feldspar are tectosilicates. Inosilicates are fundamental components in igneous and metamorphic rocks, and their study is crucial for understanding geological processes and mineral origins.