Tussah

Tussar silk (alternatively spelled as Tussah, Tushar, Tassar, Tussore, Tasar, Tussur, Tusser and also known as (Sanskrit) Kosa silk) is produced from larvae of several species of silkworms belonging to the moth genus Antheraea, including A. assamensis, A. mylitta, A. paphia, A. pernyi, A. roylei and A. yamamai. These silkworms live in the wild forest in trees belonging to Terminalia species and Shorea robusta as well as other food plants like jamun and oak found in South Asia, eating the leaves of the trees they live on. Tussar silk is valued for its rich texture and natural deep gold colour, and varieties are produced in many countries, including China,India, Japan, and Sri Lanka.

In order to kill the silkworms, the cocoons are dried in the sun. There is a variation where the silkworms are allowed to leave before the cocoons are soaked in boiling water to soften the silk and then reeled. Cocoons are collected, which are single-shelled and oval in shape, and are then boiled to extract the silk yarn from it. Boiling is a very important part in the manufacturing of silk as it softens the cocoon and makes the extraction of silk easier. In conventional sericulture, the cocoons are boiled with the larvae still inside, however if the cocoons are boiled after the larvae have left them, the silk made is then called by 'Non-Violent silk' or 'Ahimsa silk'. In China, the silks are given different names when silkworms are reared on different plants, as the diet of the silkworms has an effect on the quality of the silk (e.g., silk from larvae on wild mulberry is called zhe, while those on the oak Quercus dentata produce hu).

Tussar silk is considered more textured than cultivated Bombyx or "mulberry" silk but it has shorter fibres, which makes it less durable. It has a dull gold sheen. As most of the cocoons are collected from the forest, it is considered by many as a forest product.

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Wikipedia