I just came across this photo on the Horse Hub posted by Deb Foale. It shows the blood circulation in the legs and hooves of a horse wearing one nailed-on metal shoe, on the front right hoof. The other three hooves are barefoot. This was shared with Deb by her farrier. Certainly an interesting part of the barefoot vs shod argument.
Medicine Hat is the name applied to horses exhibiting a unique and rare pattern of color. Being mostly white in body, Medicine Hats have color on their ears and top of the head, which resembles a bonnet or hat.