Mullite, a silicate mineral composed of 3Al2O3·2SiO2, with 71.8 wt.% Al2O3, plays a critical role in the development of high-temperature materials due to its unique properties. It exhibits a high melting point of 1810°C, accompanied by low thermal expansion coefficients and remarkable mechanical strength, with a tensile strength of 62 MPa. These characteristics render it highly effective in applications requiring refractory materials that can withstand elevated temperatures. Although naturally occurring mullite is rare, found only in certain argillaceous inclusions from the Cenozoic Era in Scotland, synthetic mullite is widely manufactured for industrial uses. This is achieved by fusing silica sand or diasphoric clay with bauxite in an electric furnace. Mullite is extensively utilized in hot blast stove checker bricks, melting and firing processes, and as a refractory material in various industries, including the steel and electronic industries, where it serves as protective coatings, electronic substrates, chemical crucibles, and extruding dies. Its low, consistent coefficient of thermal expansion and resistance to flame and molten ash make it suitable for components that require a stable performance at high temperatures. Additionally, foamed mullite is applied for creating lightweight, heat-resistant structures, and precursors like calcined kyanite are sometimes used to introduce it into ceramic products containing alumina and silica, ensuring it remains a staple material in both traditional and modern high-tech applications.