I can get a pretty good sense of a person by looking into their eyes. Eyes that smile and seem like a deep well immediately reveal a person's warmth, while eyes that appear like a stone wall reveal a person's callousness.
Although this may be true 99% of the time, sometimes one meets a person with "stone wall" eyes who turns out to be remarkably kind.
Have you ever found this to be the case?
UPDATE: Yitz of Heichal Hanegina provided these pictures based on his comment: