What is Meant by “Raw Silk”?

When shopping for Thai silk fabrics and other silk items, you’ll often come across the term “raw silk,” and you may be wondering what exactly is meant by this term. When silk fiber is produced by the silkworm, it contains a gum component. If this gum hasn’t been removed yet, then we call the material “raw silk.”

How Can You Tell if Silk is Raw Silk?

Close up of raw Thai silk showing irregularities in the fabric

Close up of raw Thai silk showing irregularities in the fabric

Raw silk will be slightly uneven in width and contain small nobs or nodes in the threads. It has a low level of shininess, but when you run your hand over it it feels smooth to the touch. However, you’ll also notice the small bumps that give raw silk a slightly uneven texture.

In addition to this, raw Thai silk and other raw silk fabrics will have a characteristic odor which is difficult to describe. It’s a subtle, fragrant yet earthy scent—not at all unpleasant.

Raw silk contains a gummy substance in the tread, and this causes small amounts of dust to stick to the fabric, which diminishes the luster of raw silk when compared to more pure varieties of silk fabric.

What’s the Process of Weaving Raw Silk?

To separate our the threads that are spun into a cocoon, these must be placed into hot water to loosen them up. Actually, the individual filaments or strands of raw silk start out much too thin to be used for weaving fabric. And so a number of strands must be spun together to produce a tread that can be successfully woven. Traditionally this is done by hand, and the thread is collected on a wooden spool.

When the cocoons are submerged in hot water, workers will use a small brush to poke at them until a loose thread catches on the brush and can be used to unravel the whole cocoon. Several of these cocoons will be unraveled at once and the strands spun together into a slightly thicker thread that is a good width for weaving. A traditional reeling method uses a foot pedal powered reel to wind the strands together and collect the resulting thread on a spool. Each cocoon produces about a strand of raw silk that is about 300 meters long.

Raw Thai silk scarf

Raw Thai silk scarf

Coloring Raw Silk with Natural Dye

Raw silk in it’s natural state can be anything from a dull gray or off-white to a bright yellow color. To make it suitable for decorative fabrics it must be dyed to take on various colors. It’s preferred to use dyes produced from natural materials, but these days many fabrics are made from raw Thai silk that has been colored using artificial dyes.

One characteristic of raw Thai silk that you’ll notice is that it will appear to be slightly different colors based on the light and the angle you view it from. The fabric will also seem more of less lustrous based on the viewing conditions.

This makes raw silk a very appealing fabric choice, especially for silk scarves. When draped loosely around your neck or shoulders, a raw silk scarf will present multiple shades of color to the viewer due to the various reflective angles that it gives the light.