Originally Posted by Graces7
I tend to agree. the 4 pieces are of equal length which tends to contraindicate a Cross, and the central indent ( Monastic Historian here)
Although that area? Have you any more info? I think I know where from my time in the area.
Gleann Fan, sometimes called Gleanfahan. Basically, the hillside up from the Stonehouse restaurant that goes up and over Slea Head and down to (approximately) Dun Mhor. The stone in question's about 1/3 the way up, before the turnoff for Sleibh Eolar.
I agree that it's a millstone, there are a fair amount of those around.
The Fan river 'valley' obviously was settled for some time, and a mill on the river wouldn't be surprising. There are a lot of beehive huts, some reconstructed, as well as granaries and field walls in the area. If Ireland had any money for serious archaeological investigations, I think that area would be good for about a dozen PhD theses