You can get very hot, small blue flames from source as simple as hard wood (oak)charcoal. Some years ago, a neighbor (uphill)cut down a beautiful, hugh oak--(the roots were cracking the foundation of his house, but..)
We got all the wood (a 5 year supply, but we didn't make fires often).
One cold holiday, we did make a fire, and there was plenty of wood left in the grate at the end of the evening.. so we doused the fire with water, and covered it with a fire proof blanket, closed the damper (and the glass doors on the fireplace) and went to bed.
the next day, we had chunks of charcoal.
our next fire, which we started with the charcoal, was really hot..the iron grate in the fireplace became white hot, and was soft enough to deform.
many homes and fireplaces in england were designed to burn charcoal (and were easily retro-fitted to burn sea coal) not logs, or wood.
charcoal fires give you gem like blue flames. (as does good hard anthracite coal, in a well layed fire!)
Walter Pater
