I've never tried to ignite one from a spark, but they burn well when lighted from a flame. They produce a nasty black smoke, but you get a long-lasting hot flame and while burning they secrete a flamable oil that helps ignite your fire wood. They are waterproof and compact and easy to store. You can wrap one or more around your lighter to keep them handy. I like the fat ones that are used to bundle broccoli in my grocery store.<br><br>