sillimanite, also called Fibrolite, brown, pale green, or white glassy silicate mineral that often occurs in long, slender, needlelike crystals frequently found in fibrous aggregates. An aluminum silicate, Al2OSiO4, it occurs in high-temperature regionally metamorphosed clay-rich rocks (e.g., schists and gneisses).
How is staurolite formed?
Staurolite is a mineral that is commonly found in metamorphic rocks such as schist and gneiss. It forms when shale is strongly altered by regional metamorphism. It is often found in association with almandine garnet, muscovite, and kyanite - minerals that form under similar temperature and pressure conditions.
How is kyanite extracted from the earth?
Kyanite Mining: The kyanite quartzite is drilled and blasted; secondary breaking is sometimes done with a hydraulic hammer. The ore is picked up with diesel-powered shovels, loaded into trucks, and hauled to the primary crusher.
