Archaeologists are investigating if the stone is in its original position
Archaeologist working near Glamis are aiming to expose more about the life of the Picts around Angus and the meaning of their symbol stones.
They are excavating around St Orland's stone to find out if it is standing in its original position.
The monument, which is more than 1,100 years old, has a cross on one side and images of horse riders, animals and symbols on the other.
It also features Scotland's only known Pictish carving of a boat.
If the team find evidence of the socket stone which anchored the monument to the ground they should be able to prove it is in its original position.
It stands on a rise in marshy ground on farmland, overlooking what might once have been the farthest extent of the Loch of Forfar.
Dr Kirsty Owen from Historic Scotland said: "There is a very strong connection between the monuments and the situations that they've been put in.
"It has a boat on the rear of the carving, and it would have been quite significant that it was looking out over this lake-side setting.
"It dates from a time when Pictish kings were encouraging their people to convert to Christianity.
"A stone like this would have sent out a powerful message about the increasingly close relationship between Pictish kingship and Christianity."