It would help sooo much if people provided details of where they found rocks that they want identified, together with more detailed observations. It might be lignite, which is an extremely low grade of coal and usually brown or brownish.
Does it actually burn in the sense that it smoulders for at least a short time after you remove the flame... or is it just decomposing under the action of heat? Do you see any sign of melting before it begins to smoke? Is there any ash left behind? if so, what colour? Also, what kind of odour is being given off? Does the smell remind you of anything?
thank you for help,
I didnt provide where I found it because I couldn't remember , it could be at a beach but Im not sure.
It doesn't decompose under heat ,yes it shoulder for a short time after removing the flame, couldn't see the smoke before removing the flame.
No signs of melting before it begins to smoke and no ash is left behind
The odor is earthy like strong paper smell.
What you describe would be consistent with lignite. I don't know what else it could be... especially since you aren't getting a petroleum/hydrocarbon type odour.