Real Silk Real silk is produced as the cocoon covering of the silkworm, the pupal form of the Asian or mulberry silk moth, bombyx mori . The cocoon is spun by the silk moth caterpillar of a single silk fiber that can be up to several thousand feet in length. To harvest the silk, completed cocoons are boiled or heated to kill the silkworms, then laboriously unwound into single fibers which are plied together and spun into thread or silk yarn.
Silk is extremely high in tensile strength, exceeding that of nylon.
Silk is used to make Oriental rugs because dyed silk is a fiber with rich, saturated colors, and a distinctive, almost translucent luster. Artificial Silk Artificial silk is everything billed as silk that doesn't come from the silkworm cocoon. It's not that artificial silk is intrinsically evil, it's just that the whole point of using artificial silk in a rug is to save the cost of real silk. It is not nice when this cheaper, artificial silk rug is misrepresented and sold for the price of a real silk rug. Mercerized cotton A ripening cotton boll can contain as many as 5,000 separate cotton fibers, each fiber growing from a tiny seed and formed as a hollow cylindrical sheath of as many as thirty layers of almost pure cellulose.