In Aug. of 1976 I was working in an old German cemetery in Schaumburg Illinois.  The monument was from the 1860's and it was made of marble.  We proceeded to place a stone jack underneath the base of the stone only to have the marble crumble and crash back down to the cement base.  That is when the 5' spire and the large marble vase on top of the spire snapped off.  The vase hit me squarely on my head (photos) and the spire came down to land on my arm.