As crafters, many of us take advantage of special sales on fabrics and yarns. Sometimes the fiber content of these specials may not be known.
To determine the fiber content without special chemicals or microscopes, the "burn test" is a simple, non-technical method to determine the fiber content of an unknown fiber.
WARNING - USE CAUTION This method does involve an open flame and an unknown factors of how fast and how the yarns/threads will burn. Be sure to work in a well ventilated area and over a nonflammable surface. Have a container of water adjacent to the work area. Some fabrics will ignite and melt. The result is burning drips which can adhere to fabric or skin and cause a serious burn.
You will need:
the fiber in question
a pair of tweezers
an igniter (match, lighter, etc.)
a non-flammable work surface
container of water
catch container (something that will not burn
such as an old tin can, a glass or metal baking dish, etc.)
1. To identify the fiber content of an unknown piece of fabric, cut off a piece of the fabric about 1" to 1-1/2" long by 1/8"-1/4" wide. To identify the fiber content of an unknown yarn, cut off a piece of the yarn about 1" to 1-1/2".
2. With the tweezers, hold the fibers over the catch container
3. With the match or lighter, set the fiber on fire and watch how the fiber reacts to the flame, the smell or odor of the smoke, and the appearance of the ash. Compare your observations to the chart below.
Note: If the fabric/yarn is a blend or if the fabric/yarn is treated (sizing or finishes), the burn test will product unreliable results.
How Burns** |
How Burns |
Odor |
Ash/Bead |
Fiber |
| Burns & Non Self-Extinguishing | Burns & Chars | Burning Paper or Leaves | Soft, Lacey & Gray Ash | Linen, Juts, Hemp |
| Burns & Non Self-Extinguishing | Burns & Chars - Yellow to Orange Steady Flame - Slow Burning Ember | Burning Paper or Leaves | Soft, Lacey & Gray Ash - Easily Crushed | Cotton, Ramie |
| Burns & Non Self-Extinguishing | Burns & Chars - Fast Orange Flame - Ember Will Glow After Flame Removed | Burning Paper or Leaves | Soft, Lacey & Gray Ash - Almost No Ash | Rayon |
| Burns & Non Self-Extinguishing | Burns & Chars - Yellow to Orange Steady Flame | Burning Paper or Leaves | Soft, Lacey & Black Ash | Linen |
| Burns & Non Self-Extinguishing | Burns & Melts (Sizzles) - Flickery Flame - Will Burn After Flames Is Removed | Vinegar or Burning Wood Chips | Drips and Leaves Hard, Black, Bead | Acetate, Triacetate |
| Burns & Non Self-Extinguishing | Burns & Melts, White-Orange Tip, No Smoke | Burning Meat | Hard, Black, Irregular Bead | Acrylic (Acrylonitrile) |
| Burns & Non Self-Extinguishing | Burns & Melts | Tumeric | Soft, Black, Irregular Bead | Acrylic |
| Burns & Self-Extinguishing | Burns Briefly & Chars | Burning Hair or Feathers | Soft, Gray Bead, Easily Turns to Powder When Crushed | Silk |
| Burns & Self-Extinguishing | Burns Briefly & Chars - Orange Flame - No Smoke | Burning Hair or Feathers | Dark, Irregular Ash, Turns to Powder When Crushed | Wool, Cashmere, Mohair, Alpaca, etc. |
| Burns & Self-Extinguishing | Burns Briefly & Melts - Blue Base & Orange Tip, No Smoke | Burning Celery, Burning Plastic | Hard, Gray or Brown Bead | Nylon |
| Burns & Self-Extinguishing | Burns Briefly & Melts | Burning Asphalt | Hard, Tan Bead | Olefin |
| Burns & Self-Extinguishing | Burns Briefly & Melts | Sharp, Acid Chemical | Hard, Black, Irregular Bead | Modacrylic |
| Burns & Self-Extinguishing | Burns Briefly & Melts | Sweet, Fruity Chemical | Hard, Black, Irregular Bead | Vinyon |
| Burns & Self-Extinguishing | Burns Briefly & Melts - Orange, Sputtery Flame - Black Smoke | Sweet, Fruity Chemical | Drips and Leaves Hard, Black, Round Bead | Polyester |
| Will Not Burn | Fiberglass, Asbestos, Metal |
** Non Self-Extinguishing means the test fabric/yarn does not put itself out and
you must dip it into water to extinguish the flame. Self-Extinguishing means
the test fabric/yarn extinguishes itself.