A silk moth crawls on silkworm cocoons. (123RF)

A silk moth crawls on silkworm cocoons. (123RF)

Cocoons are soaked and boiled.

Cocoons are soaked and boiled.

A worker shows the strings of silk unwinding from cocoons.

A worker shows the strings of silk unwinding from cocoons.

Silk and sackcloth are both mentioned in the Bible.

Silk and sackcloth are both mentioned in the Bible.

A tiny silk moth

A tiny silk moth

How Is Silk Made?

Posted: July 1, 2019

How do you feel about the idea of worms making your clothes? Here’s how it happens.

1. Make a cocoon. This is the silkworm’s job. It starts with spit. A silkworm—stuffed with delicious mulberry leaves—makes a long, long strand of saliva that it spins around itself as a cocoon. This will harden into a shell for the worm to hide in while it changes into a moth.

2. Boil! People steam or boil this cocoon. Then it can be unraveled into silk thread! Some cocoons are boiled with the silkworm still inside. This makes the smoothest silk. But some other silk—called “peace silk”—is boiled after the moth escapes through a hole in the cocoon. The hole breaks the silk threads, and people have to weave them together again. But the resulting nubby thread still makes cozy silk clothes.

3. Twist. Twist raw silk threads together to make a thread strong enough to knit or weave.

Silk or Sackcloth?

Have you ever felt real silk cloth? If you have, you understand why it’s so prized! Silk is soft, supple, and smooth. The best is made from silkworms that feast on mulberry leaves. (Lower quality silk comes from silkworms that eat lettuce and a plant called Osage orange.) Silk holds color beautifully. In the Bible, cloth is used to communicate ideas. Fine cloth like silk and linen expresses royalty, favor, wealth, and value: I wrapped you in fine linen and covered you with silk. (Ezekiel 16:10)

What cloth is the opposite of that? Sackcloth! It is coarse, loosely-woven, made of goat's hair, stiff, and often dirty. That’s because it may have been used for any number of things, like bagging grain or potatoes. In the Bible, people wearing it are very sad and full of grief: There was great mourning among the Jews, with fasting and weeping and lamenting, and many of them lay in sackcloth and ashes.” (Esther 4:3)