The finest silk fibers, and most of what we use today, are produced by "cultivated" silkworms grown in a controlled environment. The worms are fed a diet of mulberry leaves and increase their body size 10,000 times in their short life span. Once the cocoon is spun and before the worm hatches through the silk into a moth, the cocoon is soaked in hot water then unraveled, producing filaments that can be up to a mile long in size. The raw silk is then processed to remove the sericin - the natural "gum" that protects the fibers and causes them to stick to each other as the cocoon was spun.
Silk is a protein fiber, similar to wool or to human hair. It is only natural for silks to have some irregularities – sometimes called "slubs". This is the nature of the 100% silk fabric. Silk that has been processed can be woven or knit into a variety of fabrics. Silk will shrink, so if you are using it to construct clothing, be sure to preshrink it.
Silk often has a wonderful feel, (referred to as a "hand"), and an almost iridescent sheen that makes us think of luxury. The weight of silk is shown as "mm" – pronounced "mommy" – and varies within the different types of silk.
