Tussah Silk

Submitted by norma on Thu, 08/11/2011 - 13:02

Originally submitted by norma on Sun, 05/30/2010 - 16:00

Having bought a supply of tussah silk at Woolfest, I wasn’t exactly sure what I had bought so I was delighted to see this article by Florence Feldman-Wood, Andover, MA. USA in “The Web” from 1987. It also answers my other question about noil. I have found this to be a great fibre to use as a core when core spinning because of its texture which helps to grip the outer fibre.

….. There are two major categories of silk fibre, based on the moth that produces them. Cultivated silk comes from Bombyx mori moths that are fed white mulberry leaves, thereby producing shiny white silk. Tussah fibres are produced by a variety of wild silk moths which feed on leaves from oak trees or castor bean plants. These leaves contain tannic acid and the silk fibre is golden colour.

If you look at silk under the microscope you will see that the structure is like a ladder. This flat surface reflects light very well and that is what gives silk its lustre. If the fibres are cut or tightly twisted in spinning the lustre decreases.

Waste silk manufacturers first process the long lengths as if they were wool, combing them out into tops. This is still very lustrous. The short lengths left over from the combing, are called “noils” and are treated like cotton. They have little or no lustre but retain all the other characteristics of silk. Both cultivated silk and tussah silk are available as tops (or sliver) and as noils. Needless to say there will be a large difference in price. However a “brick” of tops, which is about 4 or 5 ounces, will go a long way and is good value for the money.

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We were also having a discussion at an early Guild meeting about silk losing its lustre when spun and a tip I learnt from Bev Tilson of Christchurch NZ who I met recently is that silk needs to be bashed when it is wet to retain its lustre.