'White' in the Bible

I saw by night, and behold, a man riding upon a red horse, and he stood among the myrtle-trees that were in the low valley; and behind him were red, bay, and white horses.

and in the third chariot white horses; and in the fourth chariot grisled, strong horses.

That in which are the black horses goeth forth into the north country; and the white go forth after them; and the grisled go forth towards the south country;