A freeze-forging method for producing sintered three-dimensional ceramic bodies, particularly magnesium aluminate spinel domes. The method comprises forming a ceramic mix of a ready-to-sinter ceramic powder and a nonaqueous liquefied sublimable vehicle having a solidification temperature from room temperature to below 200° C.; reducing the temperature of the ceramic mix to below the vehicle's solidification temperature to freeze the mix; crushing the frozen mix into powdered form; molding the frozen powder into net shape by cold forging in a mold to form a net-shaped green body preform of the desired three-dimensional shape; and densifying the green body into a sintered three-dimensional ceramic body.