My gelding has had a small sore on his face for about the last year and a half. Its about the size of a finger nail. It always looks like it heals over, but the crusties just slough off and its still there. It does bleed either. I went out today and realized he had a couple of them now on his face all about the same size, kind of greyish in color. They don't bother him even when I pick at them. At first when there was just one I thought maybe he was just rubbing there all the time and not allowing it to heal, but now there are 4 in different area on his face. Im not sure how long the new ones have been there since he gets such a thick winter coat. Has anyone else come across these or know what they are.