How do I tell if knit/jersey is 100% cotton?

[hac1224]

Title says it all...how do I tell if a knit/jersey fabric is 100% cotton or a blend?

I bought several yards of jersey a few years ago for a project I had planned and never started. Now I'm wondering if it's cotton so I could use it for jersey flats.

I've tried wetting it, and it soaks up super fast. I've also tried burning a little piece, but I don't know how to tell by that since what I've read online seems to vary. It catches fire burns fairly quickly and leaves dust/ash, not plasticy, however the edge where I blew out the flame gets a little hard like grosgrain ribbon does when heat sealed. Does that make sense?

I'm really hoping I can use this fabric, but I don't want to cut it up until I know for sure. HELP!!!!

[Rdesonia]

Originally Posted by hac1224 Title says it all...how do I tell if a knit/jersey fabric is 100% cotton or a blend? I bought several yards of jersey a few years ago for a project I had planned and never started. Now I'm wondering if it's cotton so I could use it for jersey flats. I've tried wetting it, and it soaks up super fast. I've also tried burning a little piece, but I don't know how to tell by that since what I've read online seems to vary. It catches fire burns fairly quickly and leaves dust/ash, not plasticy, however the edge where I blew out the flame gets a little hard like grosgrain ribbon does when heat sealed. Does that make sense? I'm really hoping I can use this fabric, but I don't want to cut it up until I know for sure. HELP!!!!

The edges should not be hard if it is 100% cotton.