Not your region? Change it here:

Your region:
CREMER Erzkontor Logo

Raw materials for your needs


Mullite is a crystalline material consisting mainly of aluminum oxide and silicon dioxide. It is characterized by its exceptional temperature resistance and thermal expansion properties, making it suitable for high temperature applications. Mullite has low thermal conductivity, is electrically insulating and shows high resistance to chemical erosion. Because of these properties, it is used in the ceramics industry to make refractories, insulators and as a component in high-temperature and electronic components. Mullite is an important material for applications that have to withstand extreme temperatures and chemical stresses.

Your regional sales manager

Jenny Tong

Sales Manager


Mullite is present in the form of needles in porcelain, it is used in high-mullite based products is in hot blast stove checker bricks, melting and firing processes, and is used as a refractory material, manufacture of a type of crucible, steel industry, electronic substrates and protective coatings. Artificial mullite, or synthetic mullite, a ceramic material made by a prolonged fusing in the electric furnace of a mixture of silica sand or diasphoric clay and bauxite, has the composition 3Al2O3·2SiO2, has a melting point of 1810 C, and softens at 1650 C. Mullite occurs in nearly all ceramic products containing alumina and silica but, with the exception of refractories, is seldom introduced as such except as calcined kyanite. The bricks are resistant to flame and to molten ash, and have a low, uniform coefficient of thermal expansion and a heat conductivity only slightly above that of fireclays. Normally, Mullite has very fine crystals that change form and become enlarged after prolonged heating, making the product porous and permeable. For stable high-temperature refractories the Mullite is prefused to produce larger crystals. At very high temperatures, Mullite tends to decompose to form corundum and alkali-silicate minerals of lower heat resistance. Mullite is also used for making spark plugs, chemical crucibles, and extruding dies, and a foamed mullite is used as a uniformly latticed honeycomb structure for lightweight, heat-resistant structural parts.

Other Products



Dolomite is a naturally occurring mineral and rock consisting mainly of calcium magnesium carbonate. It is characterized by a variety of properties. Dolomite comes in a var...

Fused Magnesia


By fusing in an electric arc furnace, Fused Magnesia can be produced, which along with sintered magnesia is used for refractory bricks (e.g. to line steel furnaces or cemen...

Fused MA Spinel


Fused MA Spinel, or magnesium aluminate spinel, is an inorganic material used in ceramics and materials engineering. It is characterized by a high level of hardness, therma...