Cashmere comes from goats. It is made from the long, woolly hairs that make up a goat's downy undercoat. Any goat can produce cashmere, but most cashmere is made from selected goats that produce particularly long, fine undercoat fibers.
There is no single cashmere breed though some breeds are more consistent in producing quality fiber than others. For example, Angora goats are often used to produce cashmere.
Goats selected to produce cashmere are allowed to grow their soft undercoats to maximum length during the winter. Undercoats in goats, as in dogs and rabbits, are made up of very soft, slightly crimped secondary hairs that help trap heat against the body. The hairs that make up the majority of the fur in goats, dogs and rabbits are called primary hairs or guard hairs and make up the harder, smoother top coat. Guard hairs are waterproof, but their texture is less pleasant than the downy undercoat.