A stone discovered by chance on the Isle of Canna is Scotland's first known example of a bullaun "cursing stone", experts have revealed.
Dating from about 800 AD, the stones are associated with early Christian crosses - of which there is one on the isle.
It was found in an old graveyard by a National Trust for Scotland (NTS) farm manager.
The stone is about 25cm in diameter and engraved with an early Christian cross.
It was later found to fit exactly into a large rectangular stone with a worn hole which was located at the base of the Canna cross.
NTS manager of Canna, Stewart Connor, said the importance of the stone became clear after he was notified of the discovery.
He said: "We knew of the importance of bullaun stones and that it could be a really significant find.
"Our head of archaeology confirmed a possible link to the stone at the cross and I was so excited that I went back out at 9pm that night to check whether it fitted the stone with the hole and it did."