Tussah silk is wildcrafted and may be considered organically raised.  Tussah silk, often called shantung, is made from the cocoons of wild tussah silk worms and are harvested after the saturniid moth has emerged (no insects are harmed). The wild silk worms can be found in tropical or semi-tropical forests and due to the variety of food available their silk can range in color from a light beige to a darker brown. 

Per Wikipedia:  Saturniidae Moth - The Saturniidae, collectively known as saturniids, are among the largest and most spectacular of the Lepidoptera, with an estimated 1,300 to 1,500 different described species existing worldwide (Grimaldi and Engel, 2005). The Saturniidae family includes the giant silkmoths, royal moths, and emperor moths. Adults are characterized by large size, heavy bodies covered in hair-like scales, lobed wings, reduced mouthparts, and small heads. They lack a frenulum but the hind wings overlap the forewings, producing the same function (Tuskes et al., 1996). These moths are sometimes brightly colored and often have translucent eyespots or windows on their wings. Sexual dimorphism varies by species, but males can always be distinguished by their larger, broader antennae. Most adults possess wingspans between 1 to 6 inches (2.5 to 15 cm), but some tropical species, such as the atlas moth may boast incredible wingspans of up to 12 inches (30 cm).