Amphiboles are a group of silicate minerals that are typically characterized by their elongated crystal structure and complex chemical composition. They are commonly found in metamorphic and igneous rocks and can form under high-pressure and high-temperature conditions. Amphiboles are important for understanding geological processes and can contain various elements, including iron, magnesium, and calcium. These minerals are often dark in color, ranging from green to black, and are known for their fibrous or prismatic appearance. Asbestos is a well-known group of amphiboles that has been used in construction and insulation, although it poses health risks when inhaled. Overall, amphiboles play a significant role in the Earth's crust and contribute to the diversity of rock formations.