Unlike other types of foundries, a bronze foundry specializes in the molding of bronze. The bronze casting process demands specialized skills that only a bronze foundry can provide. Only in the hands of a skilled craftsman can bronze be shaped and detailed effectively.
Bronze is an alloy composed of copper and tin (with small amounts of lead and zinc.) When headstones or plaques are made from bronze, a mold of the headstone or plaque (complete with lettering, dates, and design pattern) is prepared for pouring. Pieces of unshaped bronze are placed in a pot and melted under intense heat. Temperatures in a crucible must reach 2000 degrees in order for the bronze to properly melt. The molten bronze is then poured into the mold.
The next phase in the bronze casting process is called "chasing." The phase involves removing imperfections by lightly grinding the bronze until the desired surface texture and shape has been achieved. It's a process similar to sanding a piece of finished carpentry. The sanding gives the finished project the desired texture. After chasing, a craftsman will touch up and define any areas of detail that may not have transferred during the casting process.
In the last stages of the process, the craftsman will apply several coats of paint to the bronze piece. When the paint has dried, he or she will then rub areas of the bronze plaque with a solvent. This process (which removes the paint and exposes the top edge of both the letters and the sculpted design features) brings out the beautiful contrast between the natural bronze coloring and the painted background. Finally, a lacquer coating is applied to provide the finish.