α-Alumina for cordierite ceramics having a secondary particle size of 40-70 µm, a primary particle size of 1.5-3 µm, and a BET specific surface area of 0.5-1.5 m2/g as measured in its powder form is prepared. The prepared α-alumina is pulverized by means of a jet mill to obtain pulverized α-alumina that comprises alumina particles of 3 µm or less in an amount of 30 mass% or less and alumina particles of 15 µm or less in an amount of at least 75 mass% in relation to a particle size distribution profile of the pulverized alumina, and has a mean particle size of 4-10 µm and a +90-µm sieve residue of 50 ppm by mass or less. The thus obtained α-alumina is used to produce cordierite ceramics having a low coefficient of thermal expansion and high thermal shock resistance and exhibiting small variance in characteristics. Structures, such as catalyst carriers for use in a waste gas control apparatus and waste gas control filters, are produced from the cordierite ceramics.
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