It costs 4 refractory wax to produce a single fireproof log. However, Vanilla honeycomb can be right clicked on copper blocks to prevent them from weathering. It only costs 1 item per block, and #85 recently made it so that Forestry's Beeswax item can be used for the same purpose. Refractory wax is already relatively difficult to obtain, and I have yet to see a single player use it in survival mode. Then, refractory wax could also be right clicked onto wood blocks to make them fireproof, just like honeycomb and beeswax.