Image 1 - Showing Close-up of condition (Please note contrast in this close-up modified to better show the condition at the base of "O")
Image 2 - Showing both faces (Condition in Image 1 corresponds to the area in ellipse. Area corresponding to diamond is in another post.
Am I correct to say that there is some mortar set type of condition at the base of "O"?
But what is the ridge like formation? It seem that a bunch of metal is collecting in that area. How does this condition happen?
Any help in understanding this condition would be most appreciated.