His political ideas are from 'the Stone Age'. [=are from the distant past; are very out of date]
Their lawyer said that he would 'leave no stone unturned' in trying to find more evidence.
The researchers 'left no stone unturned' in their search for the original documents.
(..) (Rose) There, that's nice. Have to have my pictures when l travel. ls there anything you'd like ? Yes. l would like to see my drawing. (Brock) Louis XVl wore a fabulous stone, the Blue Diamond of the Crown,... ..which disappeared in . About that time old Louis lost everything, from the neck up. (..)1997 Titanic