A layered body includes: a substrate; and an oxide portion positioned on the substrate. An oxide that constitutes the oxide portion contains at least two or more rare-earth elements: silicon; and oxygen. The oxide that is contained in the oxide portion exhibits a diffraction peak derived from a (004) plane at a position of 2θ=51.9°±0.9° in an X-ray diffraction pattern, and has an apatite crystal structure. The ratio of linear expansion coefficient of the oxide that constitutes the oxide portion in an a-axis direction relative to linear expansion coefficient of the substrate is 0.15 or more and 1.45 or less.