Book or Bible

Books may be open or closed

Books remind us that headstones are documents, bearing vital statistics and
epitaphs concerning the deceased. 

Books may be open, possibly to signify that the stone is a kind of Biography, or closed in recognition of the fact that the story of the dead is over. 

The book on a headstone may be  Bible.  This identification can be confirmed  by the presence of a citation  e.g. John 19.14 or an actual scripture. 

Arabic characters identify the book as the Koran. 

A book may also signify the
occupation of the deceased, such as a minister of religion or an open book signifies a teacher.