Njerwa zazitali-zikuluzikulu za aluminiyamu ndi mtundu wa zinthu zosaoneka bwino zomwe zimapangidwa ndi aluminium oxide (Al₂O₃).
Bricks with an Al₂O₃ content exceeding 90% are classified as corundum bricks. Standards vary by country due to differences in available resources; for instance, European standards set the minimum Al₂O₃ content for high-alumina refractories at 42%. In China, high-alumina bricks are typically categorized into three grades based on Al₂O₃ content: Grade I (>75%), Gulu II (60-75%), ndi Gulu III (48-60%).
Izi ndi aluminosilicate refractory mankhwala okhala ndi aluminium okusayidi (Al₂O₃) opitilira 48%.
Ndi mtundu wa zinthu zosalowerera ndale zomwe zili ndi aluminiyamu yopitilira 48%, yopangidwa ndi mawonekedwe ndi calcining bauxite kapena zida zina zokhala ndi aluminiyamu. Amawonetsa kukhazikika kwamafuta ambiri komanso kukana kupitilira madigiri 1770. Pokhala ndi kukana bwino kwa slag, amagwiritsidwa ntchito kuyika ng'anjo zopangira zitsulo zamagetsi, ng'anjo zosungunula magalasi, ndi ng'anjo za simenti zozungulira.
Zapamwamba-zolemetsa-zofewa, zotsika-zokwera kwambiri-njerwa za alumina [1] ndi zinthu zamtengo wapatali zosaoneka bwino zopangidwa makamaka kuchokera ku special{5}}grade bauxite, fused corundum, ndi fused mullite. Njerwa zimenezi zimakhala ndi ubwino monga kutsika pang'ono-kutsika pang'ono, kukana kukokoloka kwamphamvu, komanso kukhazikika kwa kutentha kwa kutentha.
Zokwanira kuzitovu zazikulu ndi zapakati-zokulirapo, zikuyimira njira yabwino yopangira m'nyumba-zipatso zapamwamba,{2}zokwera kwambiri{2}zimene zidatumizidwa m'mbuyomu ku{3}}zitofu zoyaka moto zakudziko langa; mankhwalawa adaphatikizidwa mu "Spark Program" yapadziko lonse.