The word Kosa is derived from the Sanskrit word meaning silk. This Silk (The Finest Silk From Chhattisgarh) is created by small silkworms when they feed on the mulberry fruit and produce a kind of fine silk. This fine thread is then used to make the famous silk cloth mostly used for sarees. Kosa silk is drawn from the cocoons on the Saja, Arjun and Sal trees. It is obtained from an Indian silkworm Antheraea mylitta. This silk has great recognition for its softness and elegance. Because of its shine, luster, and softness, Kosa is quite extensively used for manufacturing traditional Indian sarees.
Bilaspur, Korba, Churi, Chanderpur, Sarangarh, Raigarh, Champa of Chhattisgarh are known for Kosa silk and its produce by Dewangan community. The production of Silk is the main livelihood for some of the villagers in the nearby districts and many of them have now started running units for producing Silk Sarees and dress materials for export.
When a few threads of the Kosa silk (The Finest Silk From Chhattisgarh) are burnt and they leave a black residue with an unpleasant odor, the fabric is supposed to be pure. However, if it leaves an ash-like residue, then the fabric is considered to be mixed with either cotton or polyester and hence not pure Kosa silk. Due to the rarity of the kosa worm and the laborious cost of cultivating it, the raw silk yarn is often blended with cotton or polyester.