(though on a heraldic shield it tends to look like this:)
but obviously the only ermine fur coat that actually looks good is the one worn by, well, an ermine:
painting by Leonardo da Vinci
When an ermine is not wearing its white winter coat it is generally called a stoat, and it comes from the same family as the weasel and the badger (gosh, I wonder what a family get-together is like an ermine's house). The black tufts of hair are from the tip of the ermine's tail, so every black streak you can see represents the life of an ermine.
Mind you, ermines are wreaking disastrous havoc on the precious wildlife of New Zealand (where some idiot introduced them to control the rabbits introduced by some other idiot) and so there I'm afraid one has to say the fewer the better.
There's a nice story told of G.B.Shaw. A lady was talking to him with great enthusiasm about the word ermine, how soft and smoothly luxurious it feels on the tongue.
He asked her what she thought of the word vermin.
Word To Use Today: ermine. This word comes from the Old French hermine, from the Medieval Latin Armenius mūs, Armenian mouse.