bkay

I bought a roll of white fabric at an estate sale today. It has no labels. After washing some of it, I think it may be a cotton/poly blend. Either that, or it's a really good cotton, as it's really smooth. Is there a way to tell?

bkay

Material Witness

Even really good cotton should be wrinkly. If it doesn't wrinkle when you scrunch it, it's not cotton.

quiltingshorttimer

There's a "burn test" although I don't know all the details--imagine you could google it. Basically a blend will burn/melt faster than a cotton.

PaperPrincess

Yes, google 'fabric burn test' to get a chart. Basically, you burn a small piece of the fabric, extinguish the flame and you can usually determine the content.
The quick check is cut a small piece, set it alight, run it under water. If the burnt edge has lumps & bumps it's a manmade fiber, like polyester. The bumps are because it melted a bit. A clean smooth edge indicates a natural fiber, like cotton.

Macybaby

I can almost always tell when I have a poly cotton fabric by the way it smells when I iron it. Could be because I use a hot iron, and you are not suppose to use it that hot on blends. I bought a large box of scraps from an estate sale, and found quite a bit of blends in it.

Bree123

It's possible that it was treated with resin. There have been report of some resin-treated cottons that stayed maintained their low wrinkle character through a few washes.

Here's the Burn Test that I use: http://www.fabricmartfabrics.com/Burn-Test-Chart.html
If you suspect it may contain synthetic or manufactured fibers, be sure to conduct the test in a well-ventilated area as the fumes can be hazardous. I hold it with tweezers over Aluminum foil that I fold up like an open box.

Cotton also rips easier than synthetic and manufactured fabrics (or blends) but that's a lot less exact than the burn test.

If it's newer, it could be rayon or a cotton-rayon blend. I've been seeing more & more of those lately; rayon looks & behaves similarly to pre-washed commercial cotton fabric. To tell rayon apart from cotton, burn a scrap of fabric you know is cotton first, then burn the mystery fabric.

garysgal

When I volunteered at a store, we had to cut up clothing for rags and they had to be 100% cotton. If there wasn't a tag to prove otherwise, we poured a little water on the fabric and if it soaked in, it was cotton. It seemed to be an accurate test.

tuckyquilter

I always take a match or lighter and burn a tiny edge of the fabric. If it curls up and leaves ANY lines it's not 100% cotton. Burnt cotton will just be like dust to touch. This method works every time.

DOTTYMO

I usually do a scrunch test in a shop and burn test at home when I'm not sure. I'm interested in trying the water test.

ManiacQuilter2

Yes, there is the old reliable burn test. I watched my best friend do it many decades ago.