Silk Fabric

Silk is a soft fabric made from threads extracted from the cocoon of the silkworm. The thread has a triangular prism-like structure of the silk fibre, which allows silk cloth to refract incoming light, creating a shimmering appearance.
Can be used to create silk cloth for tailoring.
Source: loot from monsters around your level if they are of level 60 to 75, or use Vial of Retroform on the same component of a higher level.
Use Retroform on it to receive Velvet Fabric.