Transmitted Oblique Illumination
Definition/Function:
There are two basic types of alpaca wool, Huacayo and Suri. They are differentiated by
subtile differences in the cuticle pattern
as well as differences in the cross-section. "Baby Alpaca" is a finer form of the wool
and tends to have a "wool fineness" of 70s,
an average diameter of about 20 micrometers. "Alpica Tops" tends to be the longer fiber.
Significance in the Environment:
Characteristic Features:
Alpaca hair has a refractive index along its length of about 1.56 and perpendicular to
its length of about 1.55.
It has a birefringence of about 0.01 and a positive sign of elongation.
Associated Particles:
References:
References with Photographs and/or Drawings
von Bergen, Werner (ed.), WOOL HANDBOOK, Interscience Publisher, pp. 397-413,
1963.
Hausman, Leon Augustus, "Structural charactreistics of the hair of mammals", THE
AMERICAN NATURALIST, vol. 54, no. 635, pp.496-523,
Hausman, Leon Augustus, "Recent studies of hair structure relationships", THE SCIENTIFIC
MONTHLY, pp. 258-277,
Glaister, John, A STUDY OF HAIRS AND WOOLS, Misr Press, Cairo, 1931.
(
Click here for FBI site for Animal Hair
Identification.)
