What Is Silk?

At its most basic level, silk is a protein produced and used as a building material by a number of insects and arachnids.

The silk that’s used in the textile industry, however, comes almost exclusively from the cocoons of reared-for-purpose silkworms.

It’s been a popular and sought-after fabric for thousands of years, known for its distinctive shine, its light-as-air, soft-to-the-touch texture, and its long-lasting durability. You’ll find it in a lot of cotton blend clothing from the WoolOvers range, allowing you to enjoy a dash of luxury in your everyday get-up.

How is Silk Made?

Contrary to popular belief, silkworms aren’t a particular type of animal. “Silkworm” is more an umbrella term covering a number of different insect larvae which produce silk to form cocoons during metamorphosis.

The most commonly-used silkworms are the larvae of the Domestic Silk Moth. These are reared on beds of their favourite food, white mulberry leaves, where they’ll moult four times before enclosing themselves in a cocoon made of raw silk.

If the developed silk moth were allowed to hatch, it would cause major damage to the valuable threads of the silk which make up the cocoon. To prevent this, the cocoons are either placed in boiling water or blasted with hot steam, killing the pupae inside and softening the threads’ natural binding agent so that they can be easily unwound. It takes roughly 5,000 cocoons to make a single kilogram of silk.

With the cocoons sterilised, they’re soaked in hot water and the threads are unravelled. Any clumps or imperfections are removed, usually by hand in a painstaking process. The silk is then dyed and its ultra-fine threads are separated using a warping wheel, finally bringing it to a state where it can be shipped to manufacturers.

How to Wash Silk

While silk is surprisingly durable for such a sumptuous fabric, it can become weak when exposed to heat and moisture. Don’t risk damaging your favourite piece of silk knitwear, and follow these tips from the experts…

- Never wash your silk knitwear with a detergent containing chlorine bleach, as it has a high chance of damaging the natural fibres.

- Never tumble dry, as the intense heat poses a risk of shrinking and other damage.

- When air drying, try to avoid leaving your silk in prolonged, direct sunlight. While it’s the lesser of two evils compared to tumble drying, too much sun can fade the colours, and dull down your silk’s natural shine.

- Use a mild, non-bio detergent. Ideally, you should opt for one that’s made specifically for natural yarns, for example our own tea tree oil infused wool wash.

- Check that the garment is colour-fast. While the vast majority of silk garments sold these days are colour-fast, it’s not unheard of to come across one that isn’t. To check whether it’s colour-fast or not, simply dab a small patch of the garment with a white, moist cloth. If you see any colour sticking to the cloth (even a little bit!) it’s a bad idea to wash the garment conventionally, either in the machine or by hand. Instead, take it to a good drycleaner.