Silk - 8000 years of history
Silk - 8000 years of history.
Legend has it that the secret of silk was discovered over a cup of tea - nearly 5000 years ago. As the Empress of China sat in her garden, drinking tea beneath the shade of a Mulberry tree, something fell into her cup! As she tried to fish the cocoon out it began to unravel in the liquid, and she was fascinated by the fine soft filament that she drew out with her finger.
However, there is archaeological evidence that the use of silk began even earlier - more than 8,500 years ago. At a Neolithic site near the Yellow River in China, samples of soil from burials were analysed using mass spectrometry (a sensitive chemical analysis technique). The researchers identified fragments of fibroin, the unique protein fingerprint of silk fibre, confirming that these people wore silk.1
Silk processing and weaving became highly developed in China at an early date, and although at first silk was worn only by those of high rank, eventually it became a widespread commodity with many uses - strings for bows and musical instruments, fishing lines and production of paper. By the time of the Han dynasty (200 BC – 220 AD) it was used as a form of currency. Your wages might be paid in silk and you could even use it to pay your tax bill!2
Other South Asian cultures also developed silk processing technology and textiles from an early period, although it is generally believed they utilised wild silk rather than the cultivated mulberry silk.
Persia (modern-day Iran) became a centre of silk trade between East and West under the Parthians (about 250 BC - 225 AD) as silk fabric reached the West along the overland route known as the Silk Road. Traded fabrics were often unravelled and re-woven to new designs, or with a lower thread count to create more fabric from the same yarn, often causing the fabric to be nearly transparent, to the disgust of some.
By 200 AD silk was in high demand by Roman society and it was fabulously expensive - in fact one Emperor tried unsuccessfully to cap prices as the craze for silk was draining the economy of finances! A pound of unprocessed silk dyed purple was twice the price of a pound of gold and cost more than a good racehorse - that would be about 20,000 pounds sterling at today’s gold price.3 Supply could not keep up with demand.
Although cloth was traded freely, the technology of silk production (or sericulture) was a closely guarded secret, disclosure punishable by death. This is where the next legend comes to us - that two monks risked this death penalty to smuggle silkworm eggs out of China, hidden in their hollowed out wooden staves, to bring the secret of sericulture to the Roman Emperor Justinian in 550 AD.4 Constantinople (modern Istanbul in Turkey) was by then the capital of the Roman Empire and trade in silk was tightly controlled from there.
During the Middle Ages sericulture was brought to Venice, and Italy became the European centre of luxury silk production through the Renaissance.
At this time silk in the UK would cost you 10-12 shillings a yard - a maidservant’s wages for a year (the modern equivalent about £18 000). But no maidservant would be wearing silk!
Silk weaving in France was well-established by the 15th Century and Lyon became the centre of this industry with 15 000 workers employed directly or in associated trades by the 18th Century.5
Huguenot (French Protestant) refugees came to the UK in the late 17th Century and many settled in Spitalfields in London, sharing their skills and establishing this as a centre for silk weaving in the UK.6 Macclesfield was also famed for silk weaving.
In 1710 a Countess paid £100 (two years wages for a shopkeeper) for her silk dress to party at the palace. New clothes were a requirement, and the style was designed to show off as much of the rich fabric as possible. The dress, known as a Mantua, was about 2 metres wide, held out by framed undergarments. 14 metres of fabric could be used in creating the style and it would cost the equivalent of £10 000 today.7
Even now, silk is primarily a luxury fabric. China, relying on millennia of experience in silk production, is once again the main supplier of mulberry silk filament and fabric.
So what makes silk such a valued and special fibre?
1. It is a protein. Silk and wool (or other animal hair) are proteins. Other natural fibres are plant-derived and principally cellulose. The chemical structure of the silk fibroin protein gives it unique properties (of strength, suppleness and refractivity). Silk is soft, smooth, exceptionally strong and lightweight. It has great thermal properties, feeling warm in winter and cool in summer.
2. Silk is the only natural continuous filament. A single filament can be around 1000m in length with a diameter of 10-13 microns (human hair averages 70 microns). Silk is unwound or reeled and several filaments are ‘thrown’ or very slightly twisted to hold them together to form a yarn for weaving. All other natural (and most man-made) fibres are relatively short in length and can be made into a yarn by a tighter twist so that the individual fibres hold together by friction. They are known as staple fibres.
3. A mulberry silk filament is almost transparent with a smooth surface and a triangular cross-section. This means the filament acts like a prism, refracting and dispersing the light just as drops of water form a rainbow, giving the silk its beautiful shimmer.
Maximising the unique properties of silk in my luxury scarves:
In creating my silk scarves I apply this technical knowledge to reduce surface scattering of light and to take advantage of the unique refractive qualities of the prism-shaped filament of the silk.
I use mulberry silk as it has a transparent, colourless triangular cross-section. Wild silk with its darker colour and more crescent-shaped cross-section and slightly striated surface does not have the same refractive properties.
I choose high quality reeled or thrown silk, with long filaments, rather than silk yarn spun from the shorter broken pieces. It is soft, drapes well and feels wonderfully smooth. Spun silk has a more matt appearance as it scatters the light.
I particularly chose a satin weave fabric to maximise the length of filament that can catch the light, rather than a plain or twill weave where more scattering of light occurs. I love the additional shimmer and drape of a soft satin.
My scarves are printed with high-quality dyes that penetrate the filaments. This gives translucent rich jewel-like tones and retains the refractive shimmer of the silk. Some printing processes use pigments which adhere to the surface of the fibre. Pigments obscure the surface and absorb or scatter light.
Not least, my unique designs are created to take full advantage of all these gorgeous properties of silk.
1. Gong Y, Li L, Gong D, Yin H, Zhang J (2016) Biomolecular Evidence of Silk from 8,500 Years Ago. PLoS ONE 11(12): e0168042. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0168042
2. L. Boulnois, The Silk Road, London, George Allen & Unwin Ltd, 1966.