As I was having issues with an overly large crucible, I decided to grab one of my homemade ones I had made a couple of months ago. Since I have never used a clay crucible, I made a very crucial mistake. One must TEMPER the crucible before shoving it into the fire. Clay crucibles will absorb moisture from the air, thus they must be preheated to above the boiling temperature of water to completely dry the crucible. The medieval method would simply to place the crucible next to the fire for a while until it was dry. I have a toaster oven that would have worked fabulously to do the same thing... had I managed to remember to use it.

So, as you see from the picture above, I have the crucible sitting in the fire. Almost right away the crucible began to flake chunks of material... not good. While I watched it begin to deteriorate, though not completely failing, and cranking on the blower to keep the flames up, I realized after a while my second mistake. Cellini did state to cover the crucible with hot coals as well, and I figure I probably should give that a try since after about 15 minutes of trying to get the whole thing hot enough just wasn't working. Well, covering the crucible and cranking it up for about another couple of minutes did the trick. I really didn't have anything to cast, so I poured the contents into a sand mold trough. While I did have a messed up crucible that will just need to be broken down and saved as grog, I did finally get it figured out the steps I need to make sure I have a success the next time I give this a try.

Returning to the White Bronze in this process, I found that melting it in a charcoal environment created the appropriate reducing atmosphere that I did not cause the zinc to burn. This is really, really important, as the last time I attempted to cast with this material, the flames from an oxy/acetylene torch caused the zinc to burn instead of melt. When I poured my ingot, I got a very clean chunk of metal instead of the porous mess I got last time I attempted to use it.