Red bricks

The bricks were made from clay, which is the product of the decomposition of rocks which contain alumionous minerals, such as granite, gneiss, etc. Rain water, acids in the atmosphere, sea waves, and such other agents of denundations cause the decomposition of rocks, carrying and depositing the particles along the banks of the water bodies. 

The colour of the bricks and the clay depends on the iron and chemical content of the soil. The bricks can be produced in various colours by adjusting the contents as well as by altering the baking process. 

The light red to full red or dark red bricks are made with clay that contains iron oxide with lime altogether or practically absent. The degree of the red increases as the firing temperature is raised.