Pony
hair comes from the mane of young horses and are very fine and soft.
These are the typical hair used in the traditional Cosmetic Brush. The
very finest pony hair comes from the belly of the animal and is often
blended with other hairs for less expensive watercolor and touch-up
brushes. Natural tips are used in better brushes and the rest of the
hair is cut into lengths and used in cheaper brushes. It is strong,
slightly coarse, resilient and with the exception of sheep hair, is the
most absorbent.
Pony hair is popular in Oriental watercolor and calligraphy brush
making because it can get so long. It does not have the ability to stay
together when wet, so it is often partially starched or covered with an
outside layer of sheep hair. Each hair contains numerous pockets that
trap water and color, making them especially suitable for Sumi painting.
Pony hair doesn't hold its shape well, nor does it point. It is used as
a filler to reduce the price of a brush. Horse or pony hair is most
commonly used in inexpensive school grade brushes or cosmetic brushes.
