PURPOSE: To inexpensively obtain a lightweight sintered material having high strength and high resistance to freezing and melting by mixing specific mineral powder with fine particles of glass cullet to prepare a mixture, adding a small amount of a molding auxiliary to the mixture, molding and baking.

CONSTITUTION: 50-70wt.% of powder obtained by grinding a mineral raw material consisting essentially of a high silica type clinoputyrolite having ultrafine sealed pores and/or open pores into 200-500μm particle size range is blended with 20-30wt.% of granulated slag of blast furnace which is mostly amorphous and ground into ≤100μm particles and 10-20wt.% of fine particles of glass cullet of soda ash base having ≤50μm particle sizes such as plate glass or bottle glass to give a mixture. The mixture is blended with a small amount of a molding auxiliary, pressurized while being subjected to high-frequency vibration, molded, baked at 1,000-1,200°C and sintered to give a lightweight sintered material of ceramic such as ceramic tile having high strength and high resistance to freezing and melting.