Actually, I was thinking of using them as the container. They are very large, which is why I thought it may be okay. I do pyrography on them and yes, they are flammable (though I have not yet caught one nor myself on fire ). Perhaps it is not such as good idea ~ I have put small container candles in them in the past and it works great, but I think they are too hard and too thick to use as a mold. Probably squash or unripened gourds would work better.