Silk is a natural protein fibre produced by silkworms, primarily the mulberry silkworm (Bombyx mori). Mulberry silk cocoons are typically harvested before the moth emerges, with the cocoons boiled to soften the sericin gum and preserve the long, continuous fibres.

While silk is renewable and biodegradable, conventional production raises animal welfare concerns, as most silkworms are killed during harvesting. It also involves significant water, energy, and chemical use during processing. ‘Peace silk’ or Ahimsa silk, where moths are allowed to emerge naturally, offers a more ethical alternative but is less common and results in shorter fibres.

Silk biodegrades naturally and is valued for its durability and luxurious feel, but its production remains ethically and environmentally controversial.