How to Tell Real Silk from Fake

by Elizabeth / Wednesday, 28 September 2016 / Published in Silk Identification

Methods to Tell Genuine Silk from Fake Silk

Distinguishing genuine silk from synthetic imitations can be tricky. While visual inspection and touch can sometimes offer clues, they aren’t always reliable. This article explores several methods, focusing on the most accurate and easy-to-perform tests.

Understanding the Difference Between Silk and Synthetics

Silk is a natural protein fiber produced by silkworms. This unique composition gives it distinct properties like luster, drape, and temperature regulation. Synthetic fabrics, such as polyester, are made from petroleum-based polymers, resulting in different characteristics.

Key Differences at a Glance

Feature	Real Silk	Synthetic (e.g., Polyester)
Fiber Source	Natural (silkworm cocoons)	Synthetic (petroleum-based polymers)
Luster	Pearly sheen, iridescent	Often shiny, can appear plastic-like
Drape	Flows smoothly, drapes well	Can be stiff or clingy
Texture	Soft, smooth	Can vary, often feels slick or rough
Temperature	Breathable, regulates temperature	Less breathable, can trap heat
Burn Test	Burns slowly, smells like burning hair	Melts, smells like burning plastic
Solubility Test	Dissolves in alkaline solutions	Does not dissolve

Reliable Methods for Identifying Real Silk

While several methods exist, two stand out for their accuracy and ease of execution: the burn test and the solubility test.

1. The Burn Test: A Quick and Effective Method

The burn test is a simple yet reliable way to distinguish real silk from synthetics.

Prepare a small sample: Cut a small, inconspicuous piece of fabric.
Ignite the sample: Hold the sample with tweezers or tongs and expose it to a flame (lighter or match).
Observe the burning: Note how the fabric burns and the smell it produces.

Interpreting the Burn Test Results

Observation	Likely Material
Burns slowly, self-extinguishes, smells like burning hair	Real Silk
Burns quickly, melts, black smoke, acrid plastic smell	Synthetic
Leaves brittle, crushable ash	Real Silk
Leaves hard, plastic-like bead	Synthetic

Caution: Perform this test in a well-ventilated area and take necessary precautions to avoid burns.

2. The Solubility Test: A More Definitive Approach

The solubility test is a more definitive method that utilizes an alkaline solution (such as bleach or a solution of lye/caustic soda – use with extreme caution).

Prepare a small sample: Cut a small piece of fabric.
Prepare the solution: Dilute a small amount of bleach or carefully prepare a lye solution (following safety guidelines). Always add alkali to water, never the other way around.
Submerge the sample: Place the fabric sample in the solution.
Observe the result: Observe what happens to the fabric over time.

Interpreting the Solubility Test Results

Observation	Likely Material
Dissolves completely or partially	Real Silk
Remains unchanged	Synthetic

Caution: This test involves potentially hazardous chemicals. Use appropriate safety precautions, including gloves and eye protection, and work in a well-ventilated area. Dispose of the solution properly. Bleach can also discolor some dyed silks.

Other Less Reliable Methods

While the burn and solubility tests are the most accurate, other methods are sometimes suggested but are less reliable:

Visual Inspection: Real silk often has a characteristic sheen and iridescence, but advancements in synthetic fiber production can mimic this.
Touch Test: Silk feels smooth and soft, but some synthetic fabrics can also achieve a similar texture.
Ring Test: Passing silk through a ring is often cited, but many lightweight fabrics can pass this test, regardless of their composition.

Conclusion

While advancements in synthetic fiber technology have made it more difficult to distinguish real silk from imitations, the burn and solubility tests offer reliable methods for confirmation. By understanding the unique properties of silk and utilizing these tests, consumers can make informed decisions when purchasing silk products.