What role does black sand play in building houses in rural areas at the gate?

Black sand is put in rural houses to ward off evil spirits at the door. Among the traditional customs in rural areas of our country, there is a custom called "putting black sand", which is carried out when building a new house. Putting black sand is to sprinkle black sand in front of or around the house to ward off evil spirits and pray. In rural areas, black is regarded as a mysterious and sacred color, which has the effect of exorcising evil spirits and avoiding disasters. Therefore, releasing black sand can protect families and avoid accidents and disasters, and it is also considered as a way to pray for good luck. Although this custom has gradually faded in modern society, some people still insist on it in some traditional rural areas.