I am working on a series of bronzes cast from organic burn-outs of pieces of bark.
Instead of using the lost wax process, I took the actual pieces of bark, dipped them into the slurry to build up a ceramic shell around the bark. I then put these in a furnace at high temperature (1800 F) in order to burn the bark (organic burn-out), which leaves their shape into which the melted bronze is poured.