filosilikaatit

Filosilikaatit, known in English as phyllosilicates, are a group of silicate minerals. They are characterized by their layered structure, where silicon-oxygen tetrahedra link together to form sheets. These sheets are then held together by cations such as aluminum, magnesium, and iron, often bonded to oxygen or hydroxyl groups. This layered arrangement is responsible for the distinctive properties of many phyllosilicates, including their perfect basal cleavage, which allows them to be easily split into thin flakes.

Common examples of phyllosilicates include micas, such as muscovite and biotite, and clay minerals, like kaolinite and smectite. Micas are known for their lustrous appearance and are used in various applications, from cosmetics to insulation. Clay minerals, due to their fine grain size and ability to absorb water, are crucial in soil formation, ceramics, and as adsorbents. The specific properties of a phyllosilicate depend on its exact chemical composition and the arrangement of its layers, including the presence of interlayer cations or water molecules. These minerals are widespread in the Earth's crust and are important components of many rocks and sediments.