The present invention provides a sintered body of a joined body including two or more inorganic powder-molded bodies. The sintered body includes first components corresponding to the two or more inorganic powder-molded bodies in the joined body; and a second component corresponding to a junction in the joined body, and has one or both of the features (a) and (b): (a) the second component has a surface roughness equal to or lower than that of each of the first components; and (b) the second component has, in the vicinity of a width center thereof, a transmittance equal to or higher than that of each of the first components.