Silk is a natural protein fiber, some forms of which can be woven into textiles. The best known type of silk is obtained from cocoons made by the larvae of the mulberry silk worm. The shimmering appearance for which silk is priced comes from the fibers triangular prism-like structure which allows silk cloth to reflect the incoming light in different angles.

Silks are produced by several other insects, but only the silk of moth caterpillars has been used for textile manufacture. It has triangular shaped cross section whose corners are rounded. This fiber has natural shine to it. It is smooth and has soft textured which is unlike many synthetic fibers is not slippery. It is strongest of all natural fibers however it does not lose up to 20% of its strength when wet.

This yarn is poor in elasticity, if elongated even a small amount the fibers will remain stretched. It has natural shine inherent affinity for dyes and vibrant colours, high absorbance, light weight etc. This yarn is excellent for use in warm weather and active clothing. It is also good in cold because it keeps the wearer warm.