Are there any non flammable wood or what is the slowest burning wood?

Question

Are there any non flammable wood or what is the slowest burning wood?

Answer 1

Oak or red oak is the best for a slow burning fire.

Answer 2

The denser the wood, the more slowly it can burn. That would probably make ebony the slowest (or close to the slowest) of woods to burn. The only non-flamable wood that I can think of is petrified wood. Somehow, I don't think that's what you were after, though.

Answer 3

I have some of the most flame resistant Douglas Fir as do many others that live in the area, something to do with the soil...wet or dry for years, you need a super hot fire to get it going and if you don't keep it burning super hot (500  degrees minimum stove temp)  any lower it will go out in a matter of minutes.

Strange stuff, we have lots of it around here and it is virtually worthless as fire wood.