what is badsalt

There seems to be a misunderstanding in the question. "Badsalt" is not a known term, but "basalt" is. Basalt is an extrusive igneous rock that is dark in color, fine-grained, and rich in iron and magnesium. It is formed from the rapid cooling of low-viscosity lava on the surface of the Earth. Basalt is commonly used in construction, as it is durable and resistant to weathering.