The term "BANCO" means sand in the Mandingo language, but this does not exclude the fact that it is used by almost all ethnic groups. It is obtained from a mixture of sand and water. But not just any sand, it is what is called in the jargon of local masons "pique-à-pelle", stony sand. It is from this sand mixed with water that 12 to 13 kilogram bricks are molded with which the building is built. "Pique-à-pelle" sand that also gives a brown color to the banko.