Hillbilly yes is is heat treated. Well that makes me feel better, I knapped 7 hours straight, sore fingers, 2 cuts, left arm feels like it was run over buy a truck , but I sure had fun. I used a homemade flaker, I took #4 copper wire and put it in a piece of dowel rod. I have'nt tried a deer antler for flaking yet, how do they work. I seem to dull my copper flaker pretty easy.