Whether you sport a skinny silk tie or a chic silk blouse, natural silk possesses a timelessly luxurious quality. Synthetic materials, such as polyester, provide an alternative that comes at a fraction of the manufacturing cost and doesn't require a single silkworm to make -- sometimes, however, these synthetics get a little sneaky. Look for simple textural clues to differentiate the real deal from the impostor.

Giving the material a thorough look under the light serves as perhaps the most effective way to tell silk and polyester apart. When you hold genuine silk to light, the characteristically smooth fabric features a subtle shine -- if you tilt the material, this luster changes color depending on the angle. Synthetic polyester, on the other hand, shines white no matter how you hold it.

When faced with a questionable textile, have a close look at the weave, preferably under a magnifying glass. While machine-made polyester fabrics feature a virtually perfect, even and symmetrical weaving pattern, natural silk is prone to slight flaws, variations and imperfections. Slubbing -- slightly twisted or uneven lengths of thread -- indicates the genuine article.

Real silk lets you see any patterns or prints on the reverse side of the material; polyester prints don't shine through. If the price tag seems too good to be true, it probably is -- genuine silk typically costs about six to 10 times as much as polyester alternatives.