The burn test is the simplest way to identify textile fibers. Each fiber burns with a distinct flame, smell and ash.
Wool (animal fiber)
- Burning: slow, self-extinguishing when removed from flame
- Smell: burnt hair/feather
- Ash: black, brittle crumbs that crush easily; gray smoke
Acrylic (synthetic)
- Burning: fast, keeps burning after flame removal
- Smell: pungent chemical odor
- Ash: hard black or brown lumps; black smoke, bright flame
Cotton (plant fiber)
- Burning: fast with large flame, no smoke
- Smell: burning paper
- Ash: fine light-gray powder, minimal
Polyester (synthetic)
- Burning: shrinks and melts, self-extinguishes
- Smell: slightly sweet
- Ash: hard black beads
How to do it
Hold a few fibers with tweezers near a flame; observe burning behavior, smell and ash. Work in a ventilated area and be careful. Blends show mixed characteristics — judge holistically.