Abstract: A raw material with a high content of aluminum oxide has the following composition, in weight-percent, based on dry weight: Al2O3 ?50–80% MgO ??2–15% SiO2 ??1–15% CaO 0.5–20% Fe2O3 0.5–2% Na2O 0.5–2% Al (metallic) 0.1–2% AlN 0.1–1% K2O 0.1–1.5% F 0.1–2% Cl 0.1–0.8% balance in total, not to exceed ?5% loss on ignition, not to exceed 15% The main mineral constituents of the raw material are, in weight-percent aluminum hydroxide 20–60% corundum ?-Al2O3 10–40% spinel MgAl2O4 ?5–40% Specifically, the aluminum hydroxide is present as aluminum mono-hydroxide Al2O3.H2O and aluminum tri-hydroxide Al2O3.3H2O in a weight ratio exceeding 0.25.

Abstract: A raw material with a high content of aluminum oxide has the following composition, in weight-percent, based on dry weight: 1 Al2O3  50-80% MgO   2-15% SiO2   1-15% CaO 0.5-20% Fe2O3 0.5-2% Na2O 0.5-2% Al (metallic) 0.1-2% AlN 0.1-1% K2O 0.1-1.5% F 0.1-2% Cl 0.1-0.

Abstract: A porosifying, solidification-accelerating additive for binding agent building materials consisting of Al2O3, 50-90%; MgO, 4-20%; SiO2, 0.5-15%; AlN, 0.1-5%; Fe2O3, 0.1-5%; CaO, 0.1-5%; F, 0.1-5%; Na2O, 0.1-5%; K2O, 0.1-2%; as well as in the form of metallic particles: Al, 0.1-10%; Si, 0.1-3%; Fe, 0.1-3%; balance in total maximum, 5%; annealing losses, 0.1-15%; and of mineral main constituents in the form of corumdum (&agr;-Al2O3) and spinel (MgO×Al2O3), wherein the metallic aluminum particles are enveloped by mineral transition modifications from aluminum hydroxide (Al2O3×3H2O) to &agr;-aluminum oxide, the powder comprises a particle size of at least 90% smaller than 500 &mgr;m, and the BET surface of the powder amounts to at least 10 m2/g.