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 [=are from the distant past; are very out of date]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.
(..) To be tended by monks... who will not know his identity. But his life will be safe... and yours, too. Father Godwin! The pommel stone of the sword Requiter. It is his by right. If you hope to identify him... in years to come by means of this stone... so can his enemies. Twenty years passed. Queen Enid had died... but the rumor that she had given birth to a son... (..)1958 The Vikings