Leather 101 - Cowhide
A cow is a large animal with thick skin. There are two main layers to cowhide. The corium is the bottom layer of skin and contains thin, flexible fibers. The grain is made of strong, tightly packed fibers. The grain is the top layer of skin and bears the scars and blemishes of the animal's life. Because cowhide is so thick, it must be cut down into thinner slices to be made useful.