How to Tell The Difference And Test Between Real
How to tell the difference and test between real and fake silk
These days there are many different kinds of manmade and mixed fibres which can imitate the look and feel of silk (though no material can quite match the qualities of real, pure silk). There are a few simple methods one can use to test if a silk product is in fact pure and true silk.
1. By feel and appearance
The weave: Silk is a natural and handmade fabric, and this can be seen upon close inspection of the material. If it is real silk you should be able to see small flaws and parts where the thread has been joined together. Machine made fibres such as polyester do not have these irregularities.
The shine: Silk has a natural shine and lustrous quality that also varies depending on which way it is held to the light since there are two directions to the fibre, the wrap and the weft. Fake silk will not display any difference in lustre like this since the fibres are all continuous and coherent.
However, recent advances in manmade fibres have made the above visual tests less reliable so it is best to use one or both of the following destructive techniques:
2. By burning the silk
Take a small sample of the material and put a flame to it (a cigarette lighter is preferable to a match since there is less flame odour). If it is real silk, the flame will go out as soon as the lighter is taken away. The threads should ball up and turn to ash. Because silk is made from natural protein fibres it will smell similar to burning hair and leave a very fine ash that is black and crispy.
If it is not real silk, the material will continue to burn after the lighter is taken away. It will drip and melt, and form small balls of material at the end of single threads that are burned. It will create black smoke and will not smell like burning hair. Rayon is a popular silk substitute and is made from cellulose, which means it smells like paper when it is burnt.
If the material is a mixture of real silk and other fibres it is possible to see this in the burning test, as a mixture of fibres will produce a mixture of the above two results.
3. By chemical testSilk is made from natural protein fibres and like the burn test, this can also be chemically tested. There is a chemical test which can differentiate between cellulose and protein based materials. A test solution can be formulated by mixing 16g of copper sulphate (CuSO4) in 150cc of water, with 10g of glycerine and caustic soda (NaOH) added until the solution goes clear. When a small sample of real silk is added to the solution it will dissolve, whereas imitation cotton, nylon, polyester and rayon will not.Here at Orchid Silks we take great care to ensure all our products are manufactured from pure silk (100% where indicated) and we fully guarantee this. We check every order to ensure the material corresponds exactly with the specification.