The Lost wax method of casting is a long process involving many skilled craftsman. 

The cost of bronze reflects not only the value of the metal, but the time and effort each piece requires to create.

IHere I am working on Origin, smoothing an oil based clay over a styrofoam armature.	When the piece is completely sculpted, an initial mold (mother mold) is made of rubber or silicone.  The ridges are shims that will allow the mold to come apart in sections.	The rubber is then covered with a fiberglass or plaster jacket to give support and maintain the shape of the sculpture.
The sections of the mold are filled with brown wax.  In smaller molds, the wax is poured into the mold and dumped out, leaving a thin layer of wax in the mold.	The wax is chased and sprue bars are added.  Chasing the wax means that all imperfections are cleaned up. The sprue bars, the red wax bars will form tunnels for the bronze to flow in and vents for air.	After chasing the wax, the pieces go to the shell room where they are dipped in layers of silica and ceramic solutions until a thick shell is built up.  This shell is fired in a large kiln before the bronze pour.  When the shell is heated the wax melts out.
These are videos of a bronze pour.  It was filmed at Fedde Bronze Works in Denver in 2003.  Here the furnace is heating the bronze to 3500 degrees. I just love the green flame.	Here are the molds in the kiln.  They will be placed in the pit for pouring while they are still very hot.	Here the bronze is being poured into the molds.  A large crucible holds the molten bronze.
When the bronze has cooled, the ceramic shell is removed by chisel and the metal sprue bars are cut off the piece.  Then the sculpture is ready to be welded together and the metal is chased.  This means the metal is sanded, smoothed and imperfections are removed.	The last step is the patina, or color.  The sculpture is heated and chemicals are sprayed onto the hot metal causing the metal to take on a coloration called a patina.  The color differences are acheived by using different chemicals such as iron oxide, cupric nitrate, liver of sulfer etc.