Stone at Iona
The Stone at Iona was one of the names of the Stone of Destiny. ("Rock of Ages")
This title referred to the period in the Stone's history when it was kept at Iona, where Merlin and King Pelles brought it after they used it to help bring the young King Arthur Pendragon to the British throne. This lasted until the Stone was moved to Scone, apparently in the time of Kenneth mac Alpin.