It will be seen that stone is filled with image. The Sokkuram or Seokguram, an eighth-century image in Kyongju, Korea. https://en.wikipedia.org/wiki/Seokguram#/media/File:%EC%84%9D%EA%B5%B4%EC%95%94_%EB%B3%B8%EC%A1%B4%EB%B6%88%EC%9D%98%EC%96%BC%EA%B5%B4.jpg. Contrast and detail restored.