I know I told you but these people don't know!

This is a Hologram -
A three-dimensional image, created with photographic projection. The original source would have been a white statue of Mary in the tower of the Church (which was sealed off ... why? ) which would have been projected outwards. The result is an almost ghostly image of the "real object" in its original, solid, three-dimensional state, which usually appears to be floating in space "behind" the surface of the image.

Read here - http://www.martin-richardson.com/articles/articlePage.aspx?pageId=pag0001&articleId=art0001