Got a bunch of fabric but not sure what it is? This is especially important to know if you need to dye the fabric as many dyes are very specific as to what types of fiber they dye. This is why fiber content is the very first question we will ask you if you call and ask what dye you should use. One way to find out is to do a burn test. The way that a fiber burns (or melts), the way it smells when it burns and the type of ash or other residue it leaves behind, will all provide clues to the type of fabric you have.
Before doing a burn test you should take some safety precautions. Always work in a well ventilated area—especially important if testing synthetics. Use metal tweezers or tongs to hold the fabric you are burning and make sure you have fire extinguishing materials handy, just in case. Other tips: 1) Don’t do the test when you have sinus problems or a cold and don’t use matches or refillable lighters with a strong fuel smell; a disposable lighter works best—the way the burnt fiber smells is important for identification too. Here’s a basic guide.
Cellulose (Cotton/Linen/Hemp/Rayon/Bamboo):
Ignites and burns quickly, may flare, leaves a glowing ember after flame is extinguished. Smoke is white or light colored and smells like burnt paper or leaves. Ash is light gray or white and very soft.
Protein (Silk/Wool, Cashmere, Alpaca etc):
Burns slowly and shrinks or curls away from the flame. Will not stay lit after flame is removed. Very little smoke is produced but it smells like burnt hair (wool) or feathers (silk). Ash is a gritty powder or a dark brittle, easily crushable bead.
Synthetics (Nylon/Polyester/Acrylic):
Ignites and burns quickly and can continue to burn after a flame is removed—exercise caution. Fiber may shrink from the flame, melt, and can drip (DANGER) leaving a hard plastic-like bead. Burning these fabrics will produce black smoke and hazardous fumes. Nylon smells like plastic when burnt but can also can produce a celery-like smell; Acrylics burn with a strong, acrid, chemical smell. Polyester smells slightly sweet, also with a chemical odor.