What Causes Color Variations in Saltillo Tile?
The tiles are stacked in the caves (kilns) on end, slightly overlapping so that they will not fall over. Before firing, the opening to the kiln is sealed with clay to prevent heat from escaping. The fire is started at the bottom of the cave and fuel is added to increase the heat until the proper temperature is reached. As you know, fire will not burn without oxygen, and at sometime during the firing process all of the available oxygen in the atmosphere in the cave is used up. The flame then seeks the next available source of oxygen (which it finds in the form of iron oxide in the clay tile) and burns it, flashing the exposed surfaces of the tile. The light buff color in the tile is the area that was flashed; the peach color in the tile is the area, which is shielded from the flame by other tiles. You may hear many different stories about different types of fuel used in the firing of Saltillo tile. The original source of heat used for firing Saltillo tile was burning rubber tires. Tires
