I had a couple of Stiffel Lamps from my Mom,s Estate. I though they were solid brass due to their weight. Turned out they are brass Plated. I did some research and Stiffel produced Lamps from Zinc, Pewter, and of course Solid Brass. I rendered them down in a fire pit last night. This morning i put chunks in my lee pot and it took about a hour at full temp to make a pour able ingot. Cannot figure out the metal. It,s heavy in the ingot,s. Know it,s not lead. could be a pewter as it melts under the lee pots 600 degree ceiling. Not aluminum it,s too heavy. have to cut it with a hacksaw and it has to be cut all the way through. it,s too tough for a partial cut and then snapping off the piece. I was thinking Zinc but Zinc has a 700 degree plus melting point. If it were pewter it lacks the customary grey color. Any suggestion,s as to what it might be are appreciated. Im Stumped! Thanks, SM