Perhaps they could be in an unfamiliar area and on the run for some reason. They run through dense bush and a sharp branch or leaf ( like those on a phoenix palm) cuts or pokes the eye. If not a plant it could be a piece of equipment. maybe as a youngster they were struck by a piece of flying...
In your story the post-industrial revolution era is the time and place where these mages are. I would want to consider how much your mage is integrated into ordinary post -industrial society. Do they use all the same things as regular people?Which strata of society do mages belong to? Do mages...