A temporary placeholder so you could see the few pics I was talking about :D
Will delete all later.
Ok, the tumbnails are all upside down, but if you click, it's ok.
According to my friend the history buff, the source was was a pagan site of worship, with its color due to iron. It was later supplanted by the church. Near the stone, you have this low stone, with cavities in it. Maybe for blood, we don't know. Or maybe to put some staff to open a regio ^^