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Silk is a protein fibre produced by silkworms. As a silkworm develops into an adult it feeds on leaves and then spins a cocoon from one continuous silk strand or filament, approximately 914 meters yards long. Inside the cocoon the worm changes into a chrysalis, then into a moth, which then seeks to leave the chrysalis.1 The moth achieves an escape path by secreting a liquid, which dissolves a hole in the cocoon through which the moth can then escape.[2]

Silk is a renewable natural resource and biodegradable in 100% form. Since the silk filament is a continuous thread it has great tensile strength. In woven fabrics, silk’s triangular structure acts as a prism that refracts light, giving silk cloth its highly prized "natural shimmer."[2]Silk has good absorbency, low conductivity and dyes easily.[2]

The silkworms used for wild or “tussah,” or “tasar” feed on leaves, not necessarily mulberry, and does not harm the chrysalis. Tussah silk is derived from cocoons collected after the moth has emerged naturally in the field. Because the continuous silk fibre is broken into smaller pieces as the moth leaves the cocoon, wild silk has a rougher and slubbier surface than cultivated silk.[3]Sericulture (silk farming) is labor-intensive. About 1 million workers are employed in the silk sector in China. Sericulture provides income for 700,000 households in India, and 20,000 weaving families in Thailand. Wild silk can provide a year round income for tribal people in India and some areas of China.[4]

Cocoons are soaked in [[sodium carbonate]] to soften in preparation for reeling (unwinding the filament from the cocoon). Silk fabric is then woven with the natural gum or [[sericin]] still on the yarn, acting as a natural sizing agent. After weaving, the gum is removed by boiling the fabric in alkali. This can result in a 20% reduction of the harvested weight of the silk. Some of this lost weight is added back by saturating the silk fabric in a bath of tin-phosphate-silicate salts. These processes can create a high biological load on the water, and deplete available oxygen for aquatic species if left untreated. Exposure to tin through breathing and skin contact can have acute and long-term effects on worker health if proper equipment is not used.[6]<br/>Lightweight silk fabrics (fine gauge silk) are prone to wear and are degraded by exposure to sunlight and hot temperatures. They can also be susceptible to abrasion and twisting in laundering.[7]

Although 100% silk fibre is biodegradable, the amount of time it could take for a silk product to decompose naturally and in a short period of time is dependent upon a number of conditions—including how much air, temperature and sunlight the fibre is exposed to. If the waste is buried in a landfill, it can take even longer for it to break down.[8]

| '''Promote the use of wild or “Tussah” silk.''' || • Wild silk doesn’t require the chrysalis to be killed. <br />• Wild silk provides a year round income for tribal people in India and some areas of China.[4 ] || • Due to the shorter (less prized) fibre length, wild/Tussah silk is less expensive than domesticated silk. <br />• Tussah silk fabrics have a coarser texture and are typically stiffer and heavier than domesticated silk. Wild/Tussah silk is available in small quantities.

China produces about 70% of the world's silk, followed by Brazil, India, Thailand and Vietnam, with minor production in Turkmenistan and Uzbekistan. India, Italy and Japan are the main importers of raw silk for processing.[2]

Most wild silk is cultivated in China, India and Japan.[3 ] Verification of the source of the wild silk must be provided.

Silk's natural beauty and other properties—such as comfort in warm weather and warmth during colder months— have made it sought after for use in high-fashion clothes, lingerie and underwear.[2]